Dear Anzee ~
If I was told I'd been intimate to prevent my bad behavior in other areas - in other words an unspoken threat by me t I'd be devastated. It is so selfish and cruel
Unfortunately your partner, who basically has to understand what he is doing, is simply using you. As a result you do feel that sex is all you have to give.
OK it might be a means of a little control, however it can only make you feel worse and worse over time, with less and less worth.
Any loving partner would never do that in the first place, and when told of your being triggered by sex - in other words re-injuring you - then sex would be out of the question,. Maybe the time might come you felt like it for your own sake, which would have to be a response response to love and time.
Sadly there is no love given to you, only abuse
I think you are very brave to put his cooperation on the line, there must seem to be a mountain of difficulties to overcome if you did leave, however having made that stance giving in I suspect will only make you feel worse and him more in control
I'm sure I've mentioned them before but 1800RESPECT can advise you on steps in separation, practical advice.
You are taking control of your life, that is brave and shows a great spirit which has not been broken (even if you do not think of yourself that way)
I found anger to be my ally, maybe you can too.
Please say how things go