Yes this is really difficult stuff daring, but it sounds to me like you did very well. I like that you are showing H the reality of his choices: That if he wants to end the M, (or move out, or whatever) then things between you two will be much different...
Like your boundary on ML.
Please take good care of yourself... eat, exercise and sleep well. Visit friends and family. Find new interests or hobbies to be excited about.
H really doesn't want to lose you, but it may take him a while to figure things out. You can do this!
M: A really long time. Crisis: 5 years. She's still worth it.
Life is never made unbearable by circumstances, but only by lack of meaning and purpose. -Viktor Frankl