In law issues

I've been with my fiance for 4 years now, we have a baby together and are planning to get married next year. His family has always been an issue since we got together. They wouldnt let go of his ex and would always invite her to family parties, trips, etc and didnt really like me becuase i made it clear that I would not be around anytime shes there. Not becuase of jealously  but i just felt it to be very disrespectful. When i found out i was pregnant his mom, gma, and sister moved in with her so they werent there to support me during my pregnancy. Now shes not really an issue but theres still a lot of tension between me and the whole family. I tired being nice and getting close with everyone but it didnt happen so now im really reserved when im around them and dont really talk to them much. They live about 45mins away dont seem to try to be part of my lo life. They always want us to go over there bit its a hassel traveling that far with an infant. I invite them over and they never want to come by. This always creates conflict with me and my fiancé becuase he is really close with them. I know the saying "your with him not his family" but is it really possible to be happy with someone if they dont share the same love you do with your family? Also, our car isnt very reliable and they ALL have new cars so its not only a hassle to drive out there but dangerous as well.