IS THIS fine?? let me know your opinon on my step

Hey, This(27M) is my Personal expression on someone @ this moment. I Had a friend who is my senior at my college, brother and he is my colleague now too. Its been years we spent together. He is more attracted to women. Thats very common to him. I have asked many times to him that, are you sure about your relation? He gives same answer yeah I'm clean from myside. but whenever he face breakup state he cries and get rid of that in 2 months and go for another one. behaves like nothing had happened. so the thing is... He loved one girl in college, they got separated by family (from girl side){as I know} - he cried. with in 1 year he got another girl that she ditched him with another boy - he cried. within 6 months he got into another girl \[she said no politely after getting queen like treatment\] - he cried Now she came back after 3 months again and saying don't ask anything about my past and all. and we enjoy just for now. he accepted like a cup of cake... My Question is ......... HOW ANYONE CAN DECIDE THAT SHE/HE IS THE ONE ???? I have argued with him many times and how can you be like this on any women? I have observed some mess things around the opposite gender. I feel like its better to leave him alone on & with his creepy shit. I'm Stepping out from him and want to be alone with my rules. This is what I have decided. coz I feel like love has to happen not on the interest on the Situations with women /attractions is what I feel Am I doing the Right thing ????? Just let me know your Opinon coz of Involvement of girls matter I don't wanna get involved in anyone Personally as person.