I've been where you are, and it is so bad for you. Eating every four hours is fine. We've become a nation of eating disorders and diabetics because we tend to not eat for too long, then eat too much, or eat garbage. I didn't have periods for over a year; believe me, I understand eating disorders, and you're headed that way. Your husband is the one with problems, not you. Eat good food every four hours.
Don't get me wrong; I do occasionally skip a meal because I'm simply not hungry, so don't think about it (most often, breakfast).
But you are trying to mold your body's natural needs to someone whose body's needs are definitely different from yours (supper at 3 a.m.?). Sometimes to make a marriage work you need to agree to disagree. Please eat when you need to eat. You can always sit with husband at 3 a.m. and keep him company with a few bites. Trust me, 3 a.m. is not a normal time to eat dinner, and if your body wants food at noon, 4 p.m. and 7 p.m., then feed yourself good food at those times.