Psychological Manipulation

Lately I've been researching a lot more about manipulative relationships and how to know if you're in one. I have read MULTIPLE articles and forums and I believe that I am involved with someone who is manipulating me. We've been together 2 1/2 years and I honestly do love the guy, but I'm not happy. I feel like I can't be myself and I have no say in really anything. I'm aware that I need to leave the relationship, but it's not as easy as some might think. I give my all to the guy because I love him, but it's never enough for him.