I think el barto nailed it. But to answer your initial question, the dynamics can be weird, and if it helps, I TOTALLY understand your situation and conflict. Ostensibly, my family is close. I talk to my dad (who is 77 and in Florida) every other day or so. And when I went through some shit, they were were there. My brother, same thing, but if I really think about it, we aren't that close. I got remarried, in Florida, and did the same thing to him that your brother did to you. Kind of last minute, half-assed invite. And the logic was... my remarriage wasn't a wedding in the "Four Weddings and a Funeral" sense. It was a quiet ceremony between me, my wife, and our kids. I asked my parents out of respect and because they don't really have anything conflicting (they are retired) but once it went beyond that, there were other kids, girlfriends (who I like, don't get me wrong, though they were fighting at that point) etc. and I'll be blunt: I just didn't want to deal with it. I ultimately made peace with my brother, but it is what it is. We talk every six months or so, lament how we don't talk more frequently, text each other for about a week or so, and it fades off.
You can't force this stuff. It just is what it is. Get at peace with yourself, and all else is sort of noise. If you live where you live for the right reasons (i.e. not running from stuff, not just scared to move, etc.) then that is all that matters. I'm not where I want to be (I'd rather be in Philly) but I'm where I should be, if that makes sense, and that doesn't put me in close contact with my immediate family, and for better or worse, or barring some catastrophic event, that's the way it will likely stay for the time being.