Yes you can get him back! And you can have the life that you want with him!!! I have gotten guys back many times, but you have to have faith. Do not focus on him and his new girlfriend, you will only give more energy to their relationship, making it last longer. I suggest watching some of veronica's videos in her ex back series, and playing her game. I am not sure what background you have on loa but that is a great place to start! It used to be the hardest part for me, to forgive for the initial leaving, I used to visualize and meditate letting all of that negative energy go. I know it is hard but the more that you focus on the lack of having him, the universe is giving you what you are vibrating which is more of you not having him. You have to learn to be happy and love yourself. I have kids as well, take them out and do things to get your mind off of it. Just know in your heart that you already have him back, visualize it at night, just believe he is back, and in the meantime continue to live your life and try to be positive. Believe me, I know just how hard it is, and I wish you the very best. This is only as hard as you make it though, you can choose to be upset, or choose to be happy, and putting that happy vibration out will get your man back to you much quicker!!!

Hugs! Hope everything works out for the best for you! If you need someone to talk to private message me. I am by no means an expert but it's always nice to have someone to talk to. 

Also I would really reccommend only light contact during the time where you're doing the serious mental and emotional work, contact him only over your child and nothing else, no light conversation, no joking, flirting, nothing...you want to basically ignore him right now because you're in the wrong vibration to communicate with him. Ignore him nicely though, don't make it look like you're angry or feeling negative, just make it look like you've accepted things and are moving on and need distance. Don't worry, this is actually a neat little way of proving your value and your mystery to him at the same time as being able to get into the right vibe to start dealing with him on a serious note. In that space, he'll have the honeymoon period over with in his 'relationwhatever' and start thinking about you again, which is when, if you follow the loa way and start paying attention to your intuition and inner voice, you will know to start stepping in and taking action. But always act out of confidence and love, not fear or insecurity, he will pick up the vibe. It's all about the vibe