My boyfriend and I have been together for almost a year now. We live together and we've always gotten along well. We're nice to each other, and we've always wanted to open a business together in the future. I get on very well with his family, too. Sometimes we've had arguments like couples do, but nothing serious. About two months ago, he went home for two weeks — to another country — and after he came back, he was a different person. Ever since then, he's been pushing me away, making mean comments, and we've only had sex once. Since he came back, he's said that we've become more like friends and said that maybe we shouldn't have any sex for now. I waited for a couple weeks, then asked him why this was happening all of a sudden. He said it was because of work stress and his dad's illness, then told me he's going home for another three weeks over the holidays to spend time with his father. I gave him space as much as I could, I wouldn't disturb him when he came home from work, and we barely spoke, but still he tried to pick fights.
About two weeks after he came back, he said he needed to go away to clear his head, so I said okay, and he left for the weekend without saying where he was going. When I asked him, he said he didn't know himself. I was reading all sorts of literature on relationships and I felt so lonely, but I kept remembering all the great times we've had together. When he returned, he said we should take a break in our relationship and decide what will happen after he returns from his trip home. The day after that, I found a receipt from a hotel for two people, which had been booked a week before he went away for the weekend. In other words, he lied about not knowing where he was going. There was also a bill for a restaurant and one for flowers. I was so shocked, but decided not to tell him anything because I wanted to calm down first. Yesterday, I went to download some music so I grabbed his iPod. On it, I found photos of him with another girl from that trip, and they were hugging. There was also a note basically saying that he's dreaming about her and he'll always be hers.
I was shaking, I still am. He's never said anything like that to me, nevermind giving me flowers or hotel trips. I'm so disappointed in him. He was the last person I thought would backstab me like this because he's been cheated on and dumped for somebody else. I feel so hurt and I don't understand how somebody could be so heartless. I always try to be open about any issue in our relationship, but I don't know what to do. I don't want revenge, but I want him to feel the responsibility for his actions. I don't know if I should tell him I know about it by leaving a photo of them on his nightstand? I'm going away to visit my family for Christmas, but I'm worried that if I don't let him know about all of this, I'll spend another three miserable weeks upset and then get dumped by him when he gets back. What should I do?