There is a certain bond that is made between two people when they marry each other. Now a relationship without marriage that breaks off is still hard to deal with. The difference is you have made a legal commitment to each other, so everything about marriage seems more real than when you are just in a relationship. This is why it is usually a lot more serious when a married couple breaks up. They know they have a legal tie that has to be legally broken, which means something major must have happened, or the feelings are no longer there.
Of course, a lot of the times there is such a strong bond between a couple that they can usually sort things out. The problem is, it definitely won't seem like that until your ex husband comes around to the idea. It may be that you have had an argument that has got him extremely frustrated, or that you did something wrong. Either way, love is love, and nothing should be able to break a relationship up if it is strong enough, so you need to keep committed.
Trying your thinking that you want to get my ex husband back, then you do have a tall task ahead of you. Make sure you get some professional help. Don't take freebie advice, but pay for it instead. Everyone says you get what you pay for, and that is certainly true! Simply pay a couple of dollars for an e-book and the quality will be so much better!