M.T.
I feel for you and have been there myself years ago. Some little bit of advice that helped me, and was given by my older/wiser close friend:
#1) live in the present and don't dwell on the past or worry about the future
#2) use this time for yourself, get involved in something - ANYTHING!! I'm sure you are busy with your kids, but you need some time for you. Something that makes you feel good and confident again, so you can walk by knowing he is the loser in this, not you!! Try joining an excercise class, taking an educational class, volunteering for a cause, or even get a part time job. The worst thing you can do is have too much free time on your hands. The more time anyone has to think about something, the bigger the anxiety/fear becomes over it. The majority of men I've known always seem to keep themselves so busy that they rarely dwell over relationships. That is the key!!
#3) End ALL contact with this man. The more you stay connected, the more power you give him to keep doing what he is doing and the harder it will be for him to really know what it is he wants. Don't be his security blanket, which he will then only "USE" whenever he feels vulnerable. I think staying in contact when someone is needing space (even when they reach out to you) is setting oneself up for lots of pain ahead. It wastes your time in hanging onto someone who really isn't there for you --- but you are there for him. If you cut off all ties, and do something for yourself it will definitely cause him to gain a greater respect for you as a person AND... either he will miss you and learn he can't live without you -- OR he may find he is okay with it and then, you know it really wasn't meant to be. Eitherway, you earn some self-respect and become stronger from this.
#5) Have faith in God. Every person is put in our lives for a reason - even the heartbreakers - and we must learn from each one in order to be prepared for what God has in store for us next. Even through the pain, something positive will come from it. You will be the one to determine what that is. I can't help but relate this to the song by Garth Brooks that has that line..."sometimes I thank God for unanswered prayers"... because it is so true for me. Even though we may think we want to be with someone so badly, we later find out that we were blessed to have moved on with our lives. Tomorrow is always a brighter day, but you have to be open to letting it be.
I wish you all the best and hope you get some good feedback from others that is helpful to you! And, remember to Thank God for your beautiful children - they can keep you smiling.