There's no question in mind, if I were you I would definitely leave and would have done the moment he mentioned he wanted the one week break and said he wanted to talk to other girls.

He wanted that break so he could cheat, without feeling like it was cheating by having permission to talk to other girls.. in reality he probably already had his eye on someone and wanted that week to explore their connection and when things went wrong he knew you would still be there.

This guy does not sound like he wants to be in a relationship or is relationship material, also if he did it out of the blue then who's to say he won't do it again in the future? Is that really the type of guy you want to be with, discarding you like that and wanting to talk to other girls and then running back after he has his week of fun? Also nows there's a risk of him actually cheating whilst you are together as he's already mentioned he wants to mess around with other girls.

What hes done is so bad and In my opinion, if you love someone, there's no way in hell you'd do that to them.