Am i doing the right thing by leaving?

I'm married...for the second time. I divorced over something similar to this. Let me tell you one thing...they don't change. They only get so old and ugly that women don't want them, and then they stop cheating. It's sad...I feel for you because a year and a half ago, I was in your shoes. It's just not worth it. I promise you, there is a man out there that will love you and treat you right. Let him have her and do NOT take him back. I know it's easier said than done, because I went back to my ex husband roughly 6-10 times in 5 years. He'd get caught, lie like hell to hide it, then admit it because I always had proof, cry and say he was sorry and beg me not to leave....if I didnt leave, he'd just work 10x harder for 4-6 months or more and get caught again. If I'd leave, he'd promise it wouldn't happen again...After giving him 5 years of my life, i left. Our divorce finalized on April 23rd 2010 and I met my current husband the next day. I look back now and wonder why I ever wasted my time and how I could ever put myself through that. My husband is the greatest thing I've ever known and I don't know how I ever lived without him and lived with that idiot. It gets harder before it gets better, I know. But once you get rid of him and find a good man, you'll be so thankful for me answering this question.