Spiritual Relationships Question - Growing Apart

My boyfriend and I were friends before we started dating. He was 16 and I was 18 We both liked each other before we just had an big age difference. We were "perfect" for each other in the beginning and he began to grow up and mature and find interest in things that I didn't care for. I know i should support him in everything. We have fought A LOT lately and I can't seem to figure out why. He never listens to what I say and he says that I never communicate well enough for him. I tell him things that come across as if I were telling him that everything he does is wrong. It isn't it is just the same thing over and over again that I keep having to tell him and he just can not fix it. What do I do? I want this relationship to work badly.