Speaking as someone who has been married since 1989 and separated due to deployments? I can tell you marriage isn't easy. I posted before about the 7 year itch. Tyler and I did NOT have children at that point. But it was still hard.
After kids and deployments? We had fights when Tyler came back. It was an adjustment for all of us, we had developed our own schedule and routine while he was gone and Tyler had been a war zone. Anxiety, stress, all of it. Made for tense fights and times.
What worked for us? We committed ourselves to making our marriage our priority. Even when he was deployed, we would Skype after the kids went to bed, yes, it would be early in the morning for him, but it was a commitment we made to each other. Or depending upon Tyler's schedule, I would wake up very early and Skype with him. The point is, we realized that in order to keep our marriage together, we needed to have time together, even when we were apart. Tyler needed to know what was going on in our world, and we just needed to talk.
Have we had counseling? Yes. Did it work? Yes. We have counseling recently because our oldest son was making bad decisions and we needed to wrap our arms around the problem and fix it. We go as a family. We used to go every week. Now we go once a month. It's a great way to have a neutral place to discuss things that are bothering us and even after 25 years of marriage, learn to say things so the other can understand.
You need counseling for you. You should not be crumbling inside. That just breaks my heart. Marriage is hard work. There are people who make it look easy. But you don't see what happens behind closed doors. This is the hard part. You will find out what your marriage is made of.
It is very disappointing to hear that your husband is so willing to give up. Is he not committed to the marriage? Does he believe that if he separates from you that life will magically change and be sunshine and roses? Wake up call!! It won't be. If anything, it will be more hectic and you will be forced to communicate with each other even more with kids school schedules, functions, sports, scouts, or whatever else your family does.
Tell your husband to pull his head out of his rear end. No ultimatums. But tell him he made vows, just as you did, and you plan to keep and honor them. If he can't do that? You need to know now. But he owes you a fighting chance to keep your marriage and family together. If he is hitting you or pushing you? Then I am going to say counseling probably won't help. He would need anger management help. Some men aren't willing to do that.
My next step would be to go to counseling and try it for six months before he gives up.
Good luck!