Fear - well, I have gone through fear. It possesses me off and on. I just kinda wait it out and stay on these boards. Eventually, it may take days, even weeks or months - I return to a calm space in my heart where I KNOW - not just think - I'll be ok, I am ok, no matter what. Its an inner peace. I have to keep finding it, but it's there somewhere in your heart too.
Sometimes dealing with fear is like getting over a flu for me. I'm paralyzed with this thing that is weighing me down and eventually it begins to subside and one day I notice I feel better. I have a saying that gets me through it: "When you're going through hell...keep going!" -Winston Churchill
I also have to keep my attitude with H one of love, not fear. This is just as/more challenging than facing the fear of losing him sometimes. The fear of all the pain he's caused me. The fear of more bad treatment in the future. My fear of his anger. My fear of his ability to walk out, to fight me financially in court, ETc. I actively try to change my attitude to one of love and compassion. Like - "He's too scared to work on D, he's in the middle of his mother issues, he's hurting and only knows how to express it by hurting me back" etc.
Hope this helps. I have to work on love replacing fear every day. You are not alone.