Run, do not walk, to the nearest Family Court to get an order of child support. Then speak to his commanding officer about whether the army can handle his pay so that the welfare of you and the kids are protected.
We are not talking about extravagance. He left you without money to FEED YOUR BABY!! And, then he got mad at you for taking some cash so your baby could be nourished? Your H is not in touch with reality. There is no bill, no debt that should be paid before you put food in your child's mouth. Do you realize that not providing your baby with food is, at best, neglect and, at worse, child abuse? You could be facing the child protective authorities who've come to place your baby in foster care if your H sucessfully protects his cash instead of his child!
You need to get into therapy to work out what is going on in your marriage. If you leave just to make him realize he has a great family, you may be the one who comes to a realization, not him. You may realize that he doesn't care.
All of the options you're considering have to do with the nature of the reaction you'll get from your H. Excuse me, but that's a-backwards. You don't leave to get a reaction out of him & you don't stay to "see if things will get better." You figure out what you want and need and you make your greatest effort to find out if he's the man who is willing to work with you to make a good life.
He doesn't want to talk with you, or spend timewith the family, or sleep with you? Honey, that ain't a marriage, that's a dungeon. Can you save it, as you love him? Maybe, but not by being the passive doormat you describe.
First- take care of your children's needs. They must not be left vulnerable and unprotected. You're their mother. It's your job to protect them. It's your H's job too, but if he's falling down on the job you are still responsible.
Secondly- you must take care of yourself, which means either making this marriage better or accepting that it's going nowhere and it's time to make a real, but different life for yourself & your kids. To accomplish this second task, you have to convince H of how serious you are when you say that you're either in marriage counseling with him or you're not in this marriage at all.
As for him killing himself if you go - that sounds like a controlling, manipulative tactic. If he kills himself it's because of some very deep-seated personal problems that you didn't cause. You can't be held hostage to a suicide threat.
Don't you see that he's really threatening you with homicide? You're not living life. You're in hell. Now, even your baby is being exposed to harm. You have got to do something now.