Hi ALJ, I read your newcomers post. I am sorry you find your self here. But this board can be great at times when the pain is too much to take. All of us have have that in common, pain. But it gets better as time goes by.
Right now your H seems to be clear about what he wants. If you love him and I take it you do to be here, you have to stop doing anything that strengthens his decision to leave and pushes him away. Stop begging, calling, texting, emailing etc etc. He knows how you feel by now and nothing you say adds anything in your favor.
Dont have any R talks/emails (while he is away) with him and if he starts any, try to validate his FEELINGS (dont dismiss them, show respect for what he is telling you) state you think your M is salvable, but that you cant force him to change his mind (something along these lines).
Your success at this point would be to see him wonder a little bit, have second thoughts. It takes time and you need to be patient. Focus on you and your kids, keep GALing, look your best and strong and confident when you meet, organise your life according to the new situation you are facing and dont lose hope. You say it feels fake to GAL, we say here "fake it till you make it".
Read other stories on here, try to find advice to Newcomers that Sandi2 and some others were kind enough to put together, post to some people you feel you can relate to, and keep posting on your thread, journaling at least. The more info you feel comfortable sharing with us the more people can understand what's going on and give some advice. Try to keep one thread going so people can follow your story.