will it last?

We were going out for a year and a half, when he told me that he wanted to join the army. this broke my heart it felt as though he didnt want to be with me any more. I knew he had thought bout going in the army before we were together but nothing was said until now. I thought he was being selffish in letting me fall in love with him and then doing this to me this far in the relationship. we ended up argueing bout it all the time, we split up bcoz he couldnt handle it nemre. he dumped me. I started seeing another bloke a few weeks later, this was just a rebound relationship and this other bloke knew it. we tried to remain friends, we would go out for a curry every thursday night. after bout a month and a half we ended up sleeping together, even though we tried to resist each other, we even said we couldnt see each other as mates nemore I turned in to a regular occurance. after 3mnths of being apart we got back together. after a while I learnt that when we were aprt he was seeing someone else aswell. even though I had done the same thing this really hurt me, I felt he didnt love me nemore, if he did he wouldnt of dumped me. do you fink I have the right to be hurt by him sleeping with someone else? do you think I did the right thing in getting back with him? do you think our relationship will work?