I'm new to this subreddit, I don't have nicknames for my family. This involves my jnmom (60s) and my brother and me (30s)

When I've done research into my mom's behavior, a lot of sources said that parents like her sometimes will pit siblings against each other, and I always dismissed that because while my brother and have not always been close, it never seemed like my mom was at all involved in those conflicts. In our teens, when I was in conflict with mom and he wasn't, I assumed it was because he was the stable, healthy son and I was the crazy one.

Then in my 20s, mom would tell me while we were fighting "I talked to (your brother) and he says I'm being reasonable" and stuff like that. So I was already not talking to him about this, and this made it even harder to think about talking to him, so we drifted apart and I thought it was because he chose her side.

Now we're both in our 30s, and a year ago my brother started calling me once a week (or more) because he realized he didn't have close friends and it was affecting his mental health. I was happy to oblige because I missed being close with him when we were younger, and I'm a good listener so I was able to provide him a good outlet. So we started getting close, but I avoided talking about my own issues, because they were mostly tied up in my relationship with mom, and again, I saw him as taking her side.

A few weeks ago, at the urging of my therapist, I started talking to my brother about my issues with mom. Very slowly at first, starting with the obvious then getting into stuff he wasn't necessarily aware of. Finally, I worked up the courage to ask about the times she talked to him about our arguments in our twenties.

Now, importantly, the years when that was happening, he had been going through a major health crisis. Yet another reason I didn't want to talk to him about it at the time; the little time I had with him were focused on his needs.

So I wasnt surprised that he didn't have clear memories from those years, it was a blur to him. But he said that he was (his words) "inappropriately put into a family counselor position" when we were both in our mid-teens and that dynamic persisted into our twenties. He says he tried his best to stay neutral.

My head's been spinning since I learned this. I feel like I need to reevaluate my entire relationship with my brother. All those years he was oddly distant, his annoying way of responding to emotion with logic. He was "trying to stay neutral" while mom was trying to involve him in something he shouldn't have been burdened with. My therapist agrees.

I am at a loss. I know I need to correct a lot of assumptions about our shared past. I just don't know where to start.

Thank you for reading.