Am I over reacting

[Betterthaneastenders]

Hello everyone,
I just want to see what others think of this, I was married for 20 years, I found out when I put in for a divorce that she was already married to her boss and was expecting his baby but being a Muslim Nikah marriage it's not recognised in the UK so I couldn't do anything about it.
She had the baby 3 years ago and not long after my mother put on Facebook about going to see the baby with my daughter, I questioned this as the baby had nothing to do with her and what does it make me look like her seeing a baby that she had from an affair against me.
I've just found out that my mother invited my brother to Christmas dinner, he doesn't talk to any of his 3 siblings any more and does what he can to cause problems.
My daughter approached me and said that my mum had asked her for some up to date photos of the baby as my brother was going on about her and saying that my ex's youngest was a really pretty girl.
He has never said anything about my kids before and I know it's to cause problems, I mentioned this to my sister and she spoke to our mother who sent a me a nasty message saying that they were not talking about me and to stop making everything about me.
I just don't understand why they want to be so close to the kid that came from the affair, it would still be weird if we had just separated and then she moved on, but an affair makes it all worse, on top of that, she spread lies about me to my children, social services and the police, she cost me a job I loved working in a school even though no charges were ever brought against me as the ex dropped all charges when she found out that it had gone too far, she has also stalked and messaged people I've been seeing since the divorce and caused problems so the relationships have ended.
So the women who destroyed my life, and who is continually trying to control what I do, I've got my family going on about her baby and I'm the one who has the problem, but is it me or them that's causing the problems.
Sorry for the rant but I just can't stop thinking about it now.

Is the baby your daughter's half sister or half-brother? i.e. they have the same mother, your ExW.

How old's your daughter?

(Btw your poll's not really logical - I don't know if you can edit it or not?)

Btw I'm female. You've posted on Dadsnet so please do say if you'd prefer responses from men.

My daughter is 23 and it's her half sister, and even though she sometimes doesn't realise she will go on about her sister to me, and I'll listen and talk to her, it's her sister so I wouldn't do anything to get in the way of that, it's just the fact that my mother and brother who has nothing to do with the kid keep going on about her.

You’ve asked two questions that make the answer impossible as if you say yes does that mean yes you are overthinking or yes they should stop?

I don’t think you’re being unreasonable wanting your mum and brother to not be involved. Your daughter can though as it’s her sister. Sorry for what you’re going through though. Sounds shitty.

Yeah sorry, I wasn't thinking straight when I did the poll thing, it should have made the yes and no different. Thank you for your reply it is shitty, I'm trying to get over it thr best I can, my daughter works in the same industry as her mum and she had a shitty boss, she was offered a job by her mum so she would be working for the bloke she had the affair with but she didn't want to take it and upset me, that's thinking about me and my feelings, I thanked her and told her to take it, I don't like it but I like that my daughter is better off now, and as a bonus I see her in the morning and at lunch mon to Fri, I've also encouraged my youngest to see his mum more as I didn't want him not to have his mum in his life.
It's just my family going on about the kid all the time, it's like they don't care about all of the pain and grief she put me through.