I would stress on the fact that for a marriage to work communication is the key but at the same time would not deny that sex is also as important.
For you, when you know what is not working in your marriage, why don't you work upon it? Why are you giving up? I think, you have become too comfortable with the way you are and do not want to do any effort. You have just become lazy, else why would you not want to work towards making things fine?
You are just 29, and have such a cute little member in your home and a husband, what else can anyone ask to feel motivated to live life to the fullest. Do not be mean to yourself in the first place. If you yourself feel you are over weight, then join gym, do dieting, exercise and be your fit self. Go out, have a makeover, get a new wardrobe and look good primarily for yourself. As your kid will grow, he too would want his mother to look good and smart. Same way as you would want your kid to look good, healthy and cute. So, it is unfair on your part if you think that if your husband is expecting all this from you then it is not done.
And start communicating with your husband. Make plans to go out. Go out from movies, picnics, talk more and more. Ask him his concerns, try to get into his heart as what all things bother him. Talk to him and tell him that you love him and would want things to be happy between both of you and what you expect from him and ask what he expects from you.
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