AIBU to feel frustrated by my husband's demanding adult daughter?

I think there’s a middle ground here, your dad is in a lot of cases, by definition your person, and people always joke about him being the taxi driver etc. it’s hard to know if she really insists, or whether he’s just happy to do it as a lot of dads are. My dad used to offer a lot of lifts as an adult child and he would insist. You saying she contacts when it’s both of your days off, it could be just that it’s his day off and unfortunately fir you that’s you and his’ day but she just hears ‘dads off today’. If she hasn’t friends and no mum even if she has a partner, her dad may just be the one she goes to

Weird. This would annoy me but I don’t think it will change.

Sounds like my friend’s sister who in her 50’s has been diagnosed ADHD. I think your DP is aware of her difficulties and is worried for her mental health. Let her exhaust him on your working days and on days off put a boundary down with her eg can you text me instead, your Dad is resting. Get a strategy going with your DP if possible. But the dynamic could be entrenched on both sides. Remove yourself and enjoy the peace!

She’s doing it on purpose. She wants to piss you off. I know someone exactly like this who admitted that’s why she did it. She didn’t like the person her dad married

Hopefully she’ll have children soon and have no time to send 53 text messages to anyone.

What excuses does he make for her? Does she have poor MH? Did it escalate once you got married? Have you moved into her childhood home? What do you mean by her Mum not being on the scene? He needs to help her to grow up.

Good grief. I feel for you. She’s treating him as a dumping ground for all her thoughts. I expect that when you met and she was early 20s you thought she’d grow up and grow out of it.
Men often love to feel needed and there may be some guilt there. Bit pathetic that he hasn’t tried to establish some boundaries though.
Up to you if you’re happy to always come second. Do you have any DC of your own?

I’d leave him if I were you. Leave them to it. Find someone else.

She sounds like a demanding spoilt brat who wants to mark her territory and ensure you always come second place. Unless your DH is on the same page as you and willing to put some boundaries in place your marriage will end up in trouble.

He needs to start accidentally leaving his phone at home if he’s out with you, or even switching it off/only answering when it suits him. She sounds insufferable.

Are you my mum? She’s literally in a very similar situation. Her partner of I think 10ish years has a DD who is early 30s and she is exactly the same as this. Constantly contacts him at all hours of the day demanding various things from random lifts, through to something from the shop. They live about a 30 min drive apart but he’ll just get in his car and do whatever the hell she asks. My mum gets so annoyed with him, he’s such a pushover.

I’m not sure if there’s a solution when your partner is clearly willing to be a doormat really. You can mention it’s a bit much and most parents don’t act like this but he probably won’t change.

This. I feel sorry for her partner too, knowing he comes second to her dad.

Your anger towards her is misplaced: DP is solely responsible for his actions.

common MN phrase: your problem here is your DP.

His DD’s behaviour wouldn’t be a big problem were it not for your DP’s behaviour.

‘mum isn't on the scene’ could mean a lot of things and may well be a factor in why DP is behaving as he does.

If for this reason he’s a poor partner to you, reconsider living together and/or the relationship.

Where's her partner in all this?

Yes the daughter is acting like a petulant child however the boundaries need to come from your husband. He should have made clear to her that he is stepping back a bit now shes an adult. Speak to him and if things dint change i would leave ,because do you really want to be dealing with into old age/retirement? Yes she would have gotten what she wanted by "seeing you off" but I just couldn't love like that for years until either one if us died .

Agree you need to speak with your husband. This is not normal. The problem is if it’s addressed you will be the bad guy.

Can't see much you can do here except speak to him honestly, explain how it's affecting you & ask him to put a few more boundaries in place when it comes to her requests for his time. And I suppose, reconsider the relationship if it comes to it.

Hmm she doesn't sound well. Is she vulnerable in some way? Why is your H pandering to it? It feels.....enabling in some way and I can only understand it if father feels she is incapable of managing herself.

Most adult children learn to survive without constant input from their parent. Would it be worth exploring with your H what is leading to both of them not wanting to change that aspect of their relationship?

I’m really curious as to the content of these texts…care to share? Is it newsy items or popular instagrams trends or is it typed out text messages???

Such a massive assumption. Now the OP is sidetracked into engaging with demands that she justify her whole identity as a stepmother and how she fails when the priority is surely to work out whether there is a possibly unhealthy codependency going on with DH and DSD which needs exploring.

OH wow! That's not healthy or normal. I don't think I've ever sent 53 messages in one day total, let alone to one person. I think your next holiday might have to be somewhere with no phone reception OP.
That intensity must be really negatively impacting her life as well as your DH's. She can't have time to work or study properly or have friends or a partner herself if she's so focused on your DH. If you speak to your DH I'd focus on how your SD needs to make space to build her own life. You are definitely not BU.

If it was for a shirt period, eg when she was in hospital/if she'd just lost her job, sending 53 text messages, turning up and expecting him to drop everything and drive her around would still be a bit much. As a regular thing, it's worrying-it's more than my friends with teenagers have to deal with. A lot more-they are told in no uncertain terms that dad's not a taxi!
I know everyone goes on about boundaries these days, but in a case like this, I'd have no problem setting limits, whether that be no turning up/getting lifts without prior arrangement, not calling/messaging every day etc. Well, would she like it if you or your dad expected her or her partner to be permanently on call?
Kids grow up, or should, and have their own lives-your husband is forever.

Wow, that’s a lot! What on earth is she saying? Does he reply as much? She sounds jealous of you and like she is in competition for his time/attention.

This isn’t normal but the problem is you should have addressed it before now as he will find it hard to break the cycle.

I think you should tell him this isn’t on and that she doesn’t always need to come first. She’s not a child for God’s sake.