(1) What overhead are you cutting? What real life people do you have to lean on right now?
(2) You seem to think you are being realistic regarding the biopsy. You aren't. Odds are that the results will be fine. And, if the results are not fine odds are greatly in favor of you being alive 20 years from now for almost all forms of cancer.
(3) If you need money for IVF, what is your plan? Can you or H find a job with insurance that covers it? Can you cut your other responsibilities so that you have time for a job?
(4) Fine, take a break for a few days after you meet your Monday deadlines.
"But I'm afraid H would get upset that I'm not here, looking for a job or helping around the house."
So. What if he does get upset? You are considering divorce and you are worried about doing something to take care of yourself??? This is irrational. You need a break for emotional health. FWIW, this will also help with your job search, not hinder it. IF you continue to make choices based on what it takes to try to manage H's anger and frustration, you will sabotage both your emotional health and your M. IT is YOU who controls your life, not H. Don't blame YOUR choices on him.
You resent your H greatly for his choices. But, what is in your control are your choices. If you don't have the emotional resources to support him right now, don't. You don't have to be mean in any way. Just take care of yourself first right now.
The two of you have both been going through so much that you really have no idea how you will be when things level out. Maybe H just reached the point where his emotional resources were too low to offer you support to you before you reached the same point with respect to him. It doesn't make either of you evil, just finite.
(5) Who cares if it is labeled "stress." Anti-depressants might still help. Have you told your health-care provider that you seriously feel like you are going to have a mental breakdown? Have you consulted a mental health professional?
(6) I didn't suggest that you apologize. I didn't suggest that you devalue yourself or your needs. I asked you to take charge of avoiding the stress of the fights. You can't control him, but you can walk away: "I can't handle this right now, maybe we can talk in a few days. I'm going to take some space now."
You are doing TOO much, it is hurting you and your M. So quit giving 100% and keep some for yourself, you need it.
Finally, just put any decision about a D or sep on hold. Consider it again in 6 months. Right now, your focus just needs to be on calming your life down, getting some stability, finding some peace and support. Rushing into a decision about your M is premature and unnecessary additional stress.
Look at your life -- right now all the stresses have very little to do with H. Instead, they have to do with outside demands that you have chosen to satisfy, and with two significant health issues. Getting rid of H isn't going to help with any of those things.
Try being more direct, more honest. Never do anything that you resent (and I think you've been resenting plenty lately.)