I think Open Eyes nailed it. Sometimes, it is very easy to fall in love with what we think someone to be rather than who they are. It can happen to the best of us, and is simply a testament to the power of the heart.

However, you are a mother of two, and barring that, you are a human being. You deserve somebody who isn't going to cheat on you and essentially rob you every chance he gets. That is not love, not at all. It's only in your benefit if you were to leave ASAP, and never look back. I know that is much easier said than done, but it's for the best.

Also, please don't think of yourself as pathetic, or of what you posted as pathetic. That's simply not the case. In order for someone like that to be "successful" in what they do, they have to have at least some degree of charm and attraction. I should know. My father is a perfect example of that. It is not a mark of weakness or poor judgment to fall for someone like that. Being able to realize that you've made a mistake and to pull yourself out of it, however, is a mark of wisdom and strength.

I hope I was of some help. Please take care, and know I am praying for you through this.