Can I help my parents work through their marital problems?

My parents have been together for 12 years now, lately they have been fight more than usual and I'm not to sure what to do. My dad (he's really my step-dad but I call him my dad) told me today that he can't take anymore and I don't blame him. I want them to be happy and to stay together. I'm not sure what to do and really need help. I'm afraid that they will get a divorce. My mom keeps saying how she will find someone better and I'm really worried. Please help