I too am having problems in my marriage. My husband and I NEVER have sex. It's been 7 years and he has a long list of excuses as too why we don't. I no longer care or cry about and I will tell you why.
If I have to beg, plead and cajole something out of him he obviously does not want to do, then it's not worth it. I tried to make myself something I am not in order to counter every excuse he gave, which ranged from work schedule made hime tired, stressed about money, wouldn't touch me when I was pregnant (grossed out), etc. This is just a small sampling of reasons, he got more personal as tiime has gone on and has outright blamed me for his lack of interest.
I took a step back and realized it's not me, it's him. He is the one with excuses, problems and reasons and has been the one in control of our sex life for 7 years. It only happens when he wants it too. I used to have sex with him every time he wanted too whether I was in the mood or not bcse I never knew when it would happen again. No more. If I am in the mood, we do, if not we don't. We have had sex 4 times in the past 6 or 7 months.
It's his loss, not mine. I am a great wife, mother and friend. If he doesn't find that attractive - again - his loss. I now take care of me, for me. I got very depressed at one point and stopped taking care of myself. I now make sure to do my hair and make up every day - for me. I don't shave my legs bcse we "might" have sex, i do it bcse it makes me feel good. The list goes on for the things I do to make myself feel good for me and no one else. He can either become active in our marriage or get out. Eiither way is fine with me. My sense of self worth is no longer tied up in what he thinks.
Sooooo, long story short - to all the women who told you to lose weight to make yourself more attractive to your husband - shame on them. And those women who told you he was going to cheat on you - shame on them again. I can't beilieve in this day and age women are still like this.
Moral of the story - build up your self esteem for you, just you. If you want to lose weight then go for it, but only if it will make you feel good. And do anything else you can think to do for yourself. And do not allow him to belittle you. Make yourself attractive to yourself. Size 13 is not fat. Who cares what sixe you are, you could be a size 24. Sorry for the long post, just take care of yourself and ignore the neanderthal. It's hard, but as you begin to feel better about you, you will care less and less about what he thinks.