Do I take him back

by Na...
(Canada)

I have been with my boyfriend for four years,and we are both virgins. This year things weren't going to well for us, I was withdrawing myself from him as a cry for attention, acting like i didnt care and telling him im loosing feelings. This was the first year he went on vacation without me. He knew it was a sensitive topic because my last boyfriend cheated on me in Cuba, but i trusted him and let him go. It was a family vacation with himself, his brother and a family friend who is his age. On the last night, all three boys went into rooms with three girls they had met that night about an hour before. He told me that he was drinking, and the girl took him to the room, and he had a "whatever happens happens" mentality because he was convinced i didnt care for him and was so frustrated sexually and emotionally with the relationship. She pointed to a condom on the desk and he said no, i have a girlfriend. The girl said she will never have to know and continued to rub him down there, and unzip his pants. She began to suck him off.. and nothing happened, he was completely limp he could not get it up. After about a minute he told her to just stop and that it must be his conscience but he cant do it. She told him to leave and he did. He claims to not even know her name Throughout the four years he has been an amazing boyfriend, and i never really gave him credit for it. I was constantly checking his phone and facebook and never found anything.He said he thought it would make him feel better and it was just an expirement and he learnt the hard way that it was a terrible mistake. I believe he is telling the truth about what happened but there is no way to know forsure.He never acted the same when he came back, and he never touched me. He told me two months later and said that it has been eating him up inside. I am so confused, is that considered cheating? he didnt stop her from going down there. He also hid it for 2 months, and to top it all off, he may have caught something because hes been saying his privates have been hurting,and hes been going for all kinds of tests I am so confused. I love him so much and hes begging for me back.. but i have no idea what to do. It means a lot that he couldn't hide it, or touch me or live with knowing what he did and that he came clean on his own, and he couldn't go all the way but the fact that he went in the room with her and let it happen, and how will i ever know if hes telling me the complete truth.. im lost and confused i have no idea what to do