Hard dilemma

So

My mom and me.. We get along.. Somewhat.. Like.. I usually have to contact her all the time but she doesn't do any effort for me. In fact.. She hasn't done any effort for me since I was 10 years old. Like the last year she's been coming over more often (3 times this year.. Must be a reccord) because she likes our dog. But when we talk we kind of get along fine as long as it's not about my childhood or our relationship because she's completely oblivious about it.

So she's been taking my brother on holidays for the last 10 years while leaving me behind without even asking me. I am 26 now. My brother is 23, not that it really matters but then again.. It does.. She always liked my brother better to that extend that he was allowed to hit me and throw me around without consequences for him, more than once she even punished me for complaining. But she went to a psychologist (of a center of child abuse) and her professional opinion was that my mother aparantly blocked it to that extent that she really believes nothing happened.

So I know I'll never get an apology or even any understanding for the way I feel about my growing up.

That aside.. I am now very confused.. As she just asked me to take a holiday with her...

Update: I forgot to add.. I told her I would like that but I had to check at home.

I feel like my SO nor his kids seem to be invited (she was looking up 2 person appartments) . And I'm unsure of who will pay for it but I guess that's a matter for later?

I'm honestly just really confused wether I want to take this trip or not...

I think she's not including my SO because I told her in our last conversation that he was on holiday alone with his best friend.