I'm in desperate need of relationship advice

I don't have to many friends to talk to when it comes to my relationship problems. For the last 2 weeks my bf and I have been getting in to so many fights . I am crazy in love with him , we have been together for 2 years and a half, we're both about to finish college  and have been supportive with each other but lately when we get into these nasty fights. I end up crying like always and now my tears do not mean anything to him , I've gained over 40 pounds so I havnt been eager to going out with other people , so we practically spend time with ourselves. I noticed he is starting to take me for granted. I need advice and in how 1) to get him to stop taking me for granted 2) make him realize that I do have the potential to walk away if I wanted him to 3) take me seriously when I tell him that he's hurting my feelings ,and 4) how to show him that I appreciate him and care about everything he does for me . My bf is amazing in how he's there for everything , it's just when we get into arguments he turns into the hulk and says mean things that later he says he never meant.