Unfortunately, my family has a whole lotta drama. My FH isn't much of a help because his family is pretty tight-knit and friends tend to have a biased opinion which skews mine. I'm going to try to give just little tidbits without too much personal detail- but advice on how *you'd* go about things would be much appreciated. We are having a super small DW so no room for people to avoid each other really.
Grandma, uncle/aunt (dads side): My dad had a falling out with them about 10 years ago due to them not accepting my step-mom and her children. I'm personally not the biggest fan of my SM but she's my dads wife and I get why my dad is upset/SM would 100% be attending. I was in a serious accident in 2019, and even at the hospital where everyone was, my dad didn't utter a word to them and vice versa. However, my grandma in particular would be deeply upset if not invited. These 3 are my only family where we live.
Brother (15): he's the product of a fling and not really in my life and unfortunately, my dad isn't involved much in his. His mom is someone I would never befriend to put it lightly and I wouldn't want *her* sucking up space at my wedding. Despite not being close, he is my brother above all and my other siblings will be there. He does have a relationship with the grandma mentioned above and could possibly attend if she flew with him, but other than that I can't see a way to invite a minor, without his parent(and due to the lack of a relationship, I don't think my dad counts as a parent to him here), to a wedding 4000 miles away.
Biological mom: We had 0 contact for over a decade, in large part to her abusive/alcoholic husband. Life at her home was extremely chaotic, toxic, and survival mode. Said accident above, she was contacted by grandma(without permission by me) and she's been trying to reconnect. I have her on FB but haven't seen her in person since. She wasn't there for my first wedding, my kids births, pretty much everything of my late teens-20's. If I invite her, I'd invite my grandparents on her side so she'd have someone she's comfortable with (otherwise she'd really know no one, and the divorce was messy-messy, can't say she'd have any civility even at a wedding). I would absolutely not want her husband attending, and not sure how I could state that. I'm her only child, and this is likely my last major milestone until my own kids start having them.