AIBU to feel uncomfortable if my child invites their father's mistress?

It's your wedding.

Say you want to invite your mum and dad and not have drama at it. You are refusing to pick sides but want your mum and dad and no drama.

That's it.

You do not have a relationship with this woman. It's up to your dad to pick between his wife and daughter on her wedding day.

You are not picking anyone over anyone else because you are being fair to both your parents and inviting who you want to your wedding.

Frame it as such and leave the ball in his court.

If he wants to pick his wife over you on your wedding day, let him get the fuck on with it.

Nope, just read all your updates. Shes actively nasty to your mum & not a nice person. You deserve to enjoy your day without worrying about the stress your mums going through.
Invite your dad only, if he refuses to come thats his issue.
I hope you have a lovely day.

In your place I would tell your father she is NOT invited and you will accept that he doesn't attend.

He's no loss at your wedding.
He sounds awful.
Start as you mean to go.

Invite all the people you would like to attend your wedding. Offer a +1 to your dad if it is important to you that he is there but you don't want to name his affair partner. Explain to your mum that your actions intend no disrespect to her and you are still disgusted by your dad's behaviour. Be aware, though, that you may make these compromises and your dad will still try to force others - wanting his wife seated at the top table, wanting additional members of 'their family' invited, wanting her in family photos etc.

I would always go to my child's wedding if they wanted me there. No matter who else was invited.

I'm an adult and perfectly capable of avoiding someone or just politely saying hello then not acknowledging them again. Especially on such an important day for the person I love the most.

He is putting his wife above you by giving that ultimatum. I would extend the invite to him only and if he doesn't go, cut him off. If she is not a nice woman and horrible to your mum then I can totally see why you want no relationship her and don't want her at your wedding. This is your dad's chance to prove what type of father he is. I would manage your expectations and be prepared to enjoy your day without him there.

The mistress/wife should step down, say she will not attend but still encourage your DD to go alone, purely out of respect and not to cause any more unnecessary hurt and awkwardness.
I cant imagine she'll get the greatest welcome from your DMs side of the family anyway so frankly I can't understand why she'd want to go in the first place.

I think your Dad is behaving appallingly in all of this.

He was dishonest.

If he’d wanted to move on to another relationship or not be with your Mum for any reason, he should have ended that relationship, left a little gap to get on his feet etc, and then started a new relationship. Not lied and gone behind your Mum’s back.

The consequences of a deception like that are and should be lifelong. He should have to feel awkward having to attend events alone, even if you Mum gets a new partner and brings him, that is a legitimate relationship and she should be allowed to. Your Dad should go on having to attend alone.

And as I mentioned before, I haven’t been any of the parties in this situation so no axe to grind.

She isn’t family now. She’s his affair partner so disqualified to him as someone he can just bring into the family.

I wouldn't really want to get involved but I think I would with anyone riding roughshod over people's plans and invitations.

If your dad's wife isn't invited, then she isn't invited and that's that. What decent person insists on an invite to attend a celebration that they are not wanted at? Bulldozing their way in.

So, I would stick to mum and dad and invited and that's it. Up to him and his wife what they do. I wouldn't be pushed around by them.

My mum could not have attended my wedding if I had invited my father and his current wife, for reasons I fully understand. Sometimes parental marriage breakups are civil, or relationships can be polite after many years. However in other situations (eg domestic abuse & extreme trauma) it's not possible and people (usually dads!) have to accept the consequences of their behaviour. The last place you want family drama and a distressed MOB or bride is a wedding.

The info you have posted makes it clear excluding one or both of them would be not only reasonable, but the only way forward to protect your mum (and maybe yourself as well) from unnecessary stress and distress.

This and if your dad doesn’t come, so be it. He’ll be making a very clear declaration of where his priorities lie.

i have family who would play this sort of game.
It’s your wedding. Tell your dad that it’s important both your parents are at the wedding. As it would make your mother uncomfortable, you are asking that his wife doesn’t come.

If he digs in, then I would say the invite still stands with his invite but if he chooses not to come then that’s his choice.

Your dad should have realised there would be consequences to his actions and breaking up a family by having an affair brings hardships (karma) in the future. Invite just him and if he doesn’t attend that means he chose his affair partner over his family twice.

After your updates I would say it’s your wedding and you obviously don’t want her there. I would stick to your guns that your Dad is invited but not your step mum, if he chooses not to attend then so be it.

I had this situation years ago. I didn't want new wife there as i didnt particularly like her and mum was still v hurt. Dad not happy but that was up to him. In the end he came to the wedding but not the reception. Suited everyone.

Then you've answered your own question, this isn't about your mum. You don't want someone who you don't like at the wedding and that's fine, but that is what you need to get across to your dad, keep how they met and how your mum would feel out of it.

Its your wedding so you can do as you like especially of you don’t like someone, why invite them. Personality traits aside, not quite sure why everyone is ok with your dad coming when he betrayed your mum in the worst way….why is his wife taking all the hate and flack?

When I look back at my wedding, despite trying my best to manage everyone, my fil spending the day glaring at sfil is an abiding memory. He wasn’t the affair partner but fil hated him anyway.

What was even less great was that DH wasn’t really that pleased to have sfil there and then his mum had split up with him before we were back from honeymoon 🙄

You really only have to options OP

Invite her and have your dad there
OR
Say she isn't invited and don't have your dad there. Because he picked her over his family once before and he will do it again.

In this case @Zoobalooi wouldn’t invite her or your dad actually.

My sons would never invite their step-mother to their wedding, and their father would come without her.

It's YOUR wedding so you and your partner choose who to invite.

If your Dad chooses not to come if his wife isn't there, that is his choice.

I was confused by the original post but the follow up helped me understand what's going on.

I can assume your Dad and his "mistress" (which does rather make it sound like she's some evil woman who lured him away when we all know it takes two to tango) will both be hurt and possibly angry about the snub but I get the understandable impression that it's more important to you that your mum is comfortable and content at your wedding.

You could just post out invitations. You could include a letter with your father's invitation which explains your decision and what your priorities are. e.g.

"Dad, you will notice that your invitation is just for you and that Valerie is not included in the invitation. The main reason for this is that it's of the utmost importance to me that my mum is present at my wedding day and I want her to feel comfortable. I think Valerie's presence will be upsetting to her and a distraction for the whole day. I understand that you won't be happy with this decision and you are welcome to choose to come to your child's wedding or stay at home with your wife.

"As I stand on the precipice of my own marriage, I am embarking on a life long commitment to Sam, the person that I love with all my heart and want to spend the rest of my life with. I want Sam to be embraced and welcomed into our family. I am still incredibly hurt by your choices and actions with regards to your affair with Valerie and the devastating impact that your betrayal had on my mum, my family, and my sense of trust and stability. To have her present would do a disservice to the sanctity of marriage and taint the vibe of positivity, love and celebration that I want my wedding to have.

"If you feel that you cannot bring yourself in your role as my Dad to be present on your own, I don't want you to be there. I love you and want you to be there but please understand that if you are to prioritise Valerie's happiness over mine on what should be one of the most important days of my life, you will do further irreparable damage to our relationship and I don't want that drama.

"You are an adult and it is your choice to make. Sam and I are paying for the wedding day and we are inviting the people that we love and trust to share this special day with us. I hope that you can make it."

Or something like that. I don't know.

I'm getting strong vibes that New Wife is determined to go in order to demonstrate her power and spoil it for Old Wife.

Of course OP can decide not to invite her dad's wife! There is no rule or law that says that OP has to invite her step-mother for 'balance'! Her step-mother has been extremely rude to OP's mum so why on earth would OP even want to invite her to her wedding? From what OP has said about her dad, if he decides not to attend her wedding if his wife isn't invited, it would be no great loss to OP.

I don't like being emotionally blackmailed, so what I'd say to my dad in such a situation is this: "You are invited, because you're part of my family. Your wife is not invited, because she's not a part of my family and never will be. If you choose not to come, that's your right. Unlike you, I won't be marrying again, so this is your one and only chance. Now it's up to you."

If he doesn't come, don't let it ruin your day. He's only showing you how selfish he is.