Why doesn't my husband want to be intimate with me?

My husband and I will be married for one year now and have been together for 4 years. He never seems interested in making love to me anymore. He use to be so sweet and seemed to never be able to take his hands off me. Now he doesn't seem to want to go near me. I feel like he no longer loves me because he is never intimate and he doesn't help me out with other responsibilities either. I tried talking with him but he always says the same things. For the intimacy issues he always has an excuse as to why he didn't want to (i.e. too tired, too hungry, doesn't feel well, had some beer etc) and with the marriage responsibilities he always says he'll try harder and do it tomorrow... but tomorrow never comes and he never seems to change. I feel like the guy I am with now is not the same guy I fell in love with. Help me please.
some of you asked if I had changed at all, and the answer is yes since we met I have gained a lot of weight and have been trying to take it off but am having a hard time. We go out to eat a lot together but that is really the only thing we seem to do together outside of the house in the past year or so. We both have full time jobs and have had a lot of money issues since we have been married. We argue a lot about money and chores. He did admit to me once that he has been lazy and is stressed at work, but when I asked if he wanted to talk about it he didn't. He has a really hard time opening up.