daughter of this is not fun story

I am in my early 20's and my boyfriend is in his mid 20's.We recently just got passed our 1 year anniversary. We have always gotten along and never really fought before. Money is a issue with us, but i do not live him but I am there a lot and he does ask me for money, like gas,cigaretts or just to get him through the week. For the past month now he has been acting very different towards me and I have been asking him about it and he kept saying nothing is wrong and he was fine repeatly. So we got through our year and he was still acting distant and did not acknowledge it at all, not a card a note or nothing.A week later he said he loves me but there is something really wrong and we needed a big long week break without seeing each other. He needed to focus on himself and needed time. We talked everyday, some days he was nice the next he was a a-hole. He always told me he loved me though, but he began to start drinking every night and was just really rude. After "our week" we sat down and talked it out and he just was not sure if we meshed well and all that. But i told him we can work on things and you have to believe in us and he agreed and everything. The next night he was back to him self and rude again but wanted to hang out that the next night after work to spend time together. Once i went over there we had the same talk and he said he wanted to be honest with me, and he said he was in love with me and does not want to give up but wants to be 100% sure I am the girl for him and the one he wants to marry. He needs to focus on himself and this is what he needs to do, but said it will be good for us and it will work out. He told me that he does not plan on bringing any girls home or plan on hooking up with anyone, so he wants to remain faithful and does not want to cheat. he wants us to keep our "promise" rings on still and wanted to still talk everyday and said this will work out and be stronger for the both of us. Well it has been 4 days and we have not talked at all! he has not tried contacting me at all, so now it makes me worried about whats really going on. Is he really trying to focus on himself and taking the time to think about us and everything, or is he just done with me for good and this was an easy way out? This is really who is? Just 2 months ago he wrote me a letter saying how much he loved me and saying we can see us in the future with kids, dogs and a nice and can not wait to hold my hand in marriage. Now look where we are.