I am sorry for your anxiety and worries. There are tonnes of sites on the web that can help you with that. I am not belittling what you are experiencing.It is tough. But I bet most of what you are feeling is self inflicted (rehashing the past or stressing about the future) and hence you can decide how you let that affect you.
For example your H telling you he wants a D.
Firstly you do not know that so don't assume it to be true.
Secondly if that is how he feels now and he wants to tell you that, he will. There is nothing you can do to stop it. So stressing changes nothing.
Thirdly even if he says that now, it is just a reflection of his current thinking. That can change. The proof is it changed from when ye got married till now.
Fourthly it changes nothing. Yes it confirms the bad state of your M and his intentions. But your path remains the same. You need to focus on that because only that is controllable.
You have had a long slog. Breath. Breath deep. You haveffriends here who will stand with you and help you through this.
Best wishes
R 25 years M 14 years S11 & S13 Working on it alone since Oct 2014 M in trouble a lot earlier (~2 years) Feb 2016. 1st R chat in a yr. Next R chat Aug'17 Still together