I'd like to apologize in advance for what is sure to be a long post. I'll be as concise and I can. Any advice or insight would be greatly appreciated.

My SO (30) and I (21) have been in a relationship for just over a year. This year has been the happiest of my life - he is an amazing man who I am constantly reminded of how lucky I am to have. He's bright and funny and commands any room that he walks into. We met in a community college setting where age really varies amongst students. Our difference didn't seem like a barrier when we started hanging out as friends. As our dynamic developed, I fell for him. I was tentative because of the age gap and due to what seemed like a different background to mine (growing up in the south/Midwest).

I knew he had a young son when we started dating but he told me that his son and his son's mother were living in a different state across the country and, while he planned to stay involved as much as he could, he wasn't regularly interacting with them. Several months later they moved back to a city nearby. I viewed this as a blessing for I can only image a parent's desire to see thier child grow up first hand. The kid is precious, I really enjoy how happy he makes my SO and love watching him be an awesome dad.

I'm not conflicted about my feelings toward him nor his status as a parent of someone else's child What I am unsure of is if I can maintain this relationship with his son's mother (and ex-wife) harboring such resentful feelings towards me. She insists that her and I will never be on cordial terms as she can't bear it. I believe her words to be reactionary (feeling the need to defend her turf) and that she'll change her attitude in time, but I can't be sure. Both her and their son live with his parents. To avoid drama, I don't go over to his family's house - his mother's wishes (who In all other aspects has encouraged him in our relationship together and welcomed me into her family). His son's mother has plans to move out within the next year and a half for work but nothing concrete.

I've attempted to establish my respect for his son's mother and my commitment to not hindering their coparenting. I want to be a part of my SO's life and want for this relationship to continue. I'm not sure what else I can do to make this work. If anyone has insight or personal experiences similar, I would be extremely grateful.

Thank you!