I have followed this thread too and felt compelled to post. Like everyone else, it sounds to me as though you are deeply unhappy in your relationship. Some of the things you describe remind me a bit of my exH. He was also controlling and selfish. One of the main things that made me think what I had to say might help you was how you described him crying and you feeling sorry for him and wanting to make it all right again. My ex did the same thing (his tears were crocodile tears). It's probably in our human nature to want to make someone happy again if they're crying - I'm no psychologist but I'm sure his turning on the tears are just as controlling as his constant put-downs.
My ex eventually left me although I thought about leaving him many, many times. My reasons for staying were probably similar to yours: we were married, which I felt meant that I should try to make it work; we'd been through a lot and were probably meant to be together; I thought I loved him and he made me happy (sometimes). You are not there yet so you won't appreciate this, but with hindsight I see a much different picture. Immediately after we split I was lost for a bit, although I very quickly got practical and sorted out our debts (like you, we spent money we didn't have to 'treat' ourselves - ridiculous), sold the house and set up on my own. Yes, it was daunting after 10 years with someone at a time when my other friends were having kids etc, but I grew to love that time as a single woman. I took up several interests that I'd always wanted to do, I became much more independent, I socialised - it was great.
Don't think about the future in terms of being with someone else - you need to leave him (I think) to do yourself a favour. You can be on your own and you really will be happy if you do that. You will probably, like me, look back and wonder why you didn't do it long ago.
I am now married again and really happy. We even have a DD, who is wonderful.
Not all relationships are like yours (or mine with my ex). Probably no relationship is 'perfect' - we all get wound up now and again with our DPs, but you do deserve to be a lot happier than you are now.
Please stop thinking about the ins and outs and find the courage to leave him. You know you are going to anyway (I've noticed you talk about 'when' you leave him, not 'if'). As long as you stay, he will always find a way to make you think he is trying and that he still loves you. I personally don't think he will change and I think you would be much happier if you struck out on your own.
Thinking of you X