Well, his lying to you about something like that is clue enough. Cannot base a good, firm relationship with lies. If you still wanna be with him, that is your choice, obviously. But something like that, I personally would not be able to trust him fully. You have to ask yourself, " would he do it again? Is he really sorry? " and " is he worth the hassle? "
I am sure you can find the answers as clearly as they are.
good luck to you.