A.M.
I read through most of the comments and am sorta shocked by how many people just want you to run for the hills. While I am in no way downplaying what you are feeling, you made a commitment and you took vows when you married this man (and personally, I feel that you did it again twice each time you had a child with him). The divorce rate in this country is so high because people always like to blame the other person. I am not saying that is what you are doing here, because you did a good job of stating what you weren't doing "right" in the marriage. I think that the biggest thing to remember is that there are two sides to every story. While you might feel justified in not wanting sex or not wanting to be affectionate, I'm sure those things affect him, and then he feels justified in doing (or not doing) something. It is a big circle, and unfortunately, until someone stops it, it will keep continuing. But that "stop" doesn't always have to be divorce. I went through something very similar with my husband. He was constantly unemployed and depressed and drank a lot. I pretty much wanted to run for the hills. We had a young daughter and if I would have left, I too would have left him jobless, homeless and familyless. However, we have been in counseling now for around eight months and I am starting to see the light at the end of the tunnel. We still have a long ways to go and sometimes I leave our sessions so pissed, that I still think about divorce. But I am so happy that I stuck it out because I do love him.
I suggest you watch Fireproof (movie with Kirk Cameron). Basically, it is about a young couple whose marriage is on the rocks and they are about to split. They pretty much hate each other. The husband's father suggests that Kirk try something for 30 days, before he divorces his wife. He does something nice every day for her and writes about it in a journal. During the first weeks, his actions are not reciprocated at all (in fact she is outright mean to him and cannot fathom why he is being nice to her) but eventually his actions work towards them building a future together. I know that not every story is a happy ending, but I feel like yours could be. You state that you love him very much and he is still your best friend. I think that you can work through this.
It won't be easy and there will be times when you get frustrated and pissed because you will feel like you are putting in all the effort and he is doing nothing. And honestly, that might be the simple fact at some point. But in any good marriage, you accept that sometimes you pull the load, and sometimes your partner will. Hope you figure out what is the best option for you. I will be praying for you, and if you ever need to talk, feel free to write back!