I'm really clueless what to do..?

i met a guy in my working place, he after being my friend started saying that he loved me. i didn't accept his love initially but somehow fell in love with him who had already broken his heart from his earlier affair of 5 years. he still likes her even though she's married and says he loves me too. i love him truly and couldn't leave him even after too many misunderstandings and fights. we patch up our differences soon. he has too many girl friends but says he loves only me. sometimes i feel he is very frail and indecisive. but for me he is my soulmate with whom i share my every feeling, moreover he is my first love.can i trust this guy's love for me???