Should I let him go for good..My friend/lover has dumped me as a lover and as a friend again! Since we have?

known each other at least 2x's a month over last 3 years. Everytime he walks I let him back because I know that my life is chaotic & he cant handle it. We both agree he is selfish,impatient, self centered & conceited because he works out regular & I have not for 1 1/2 & he has a great job now. I have put on some xtra weight and he let me know that he does not like. That is just the way he is. We never commited to each other & when we did it lasted for about 2 weeks before he left again. He has been with other women & I have not with other men even though we had open relationship. We have been there for each other, I more than him & I never let his faults get in the way of our *friendship*. His personality is somewhat oppressive & I found it easier to let some things go than fight. I lost myself since I have known him. Now he is dating a younger woman. She is 18 he is 55 I am 45. He says she makes him happy. I think she is to young! He is trying to remake her for himself. I am very hurt