Hi, LL. I have a similar situation in my family of origen. I'm always kind of an afterthought. So, 6 years ago I said I'm done with one of them,and I haven't had any communications with that person at all.
I love the person I cut out of my life, but I couldn't take the pain anymore.
I agree with the poster above, maybe you can try to put together a family of friends? It can start with just one person, like maybe your grandmother.
And the circle can get much larger as you add good new friends to it.
I wish you well. So sorry they're getting to you like that.

[emoji813]