My mom is 53 and is still making the same poor choices with unavailable men. Whether they cheat, were alcoholics or coke heads or addicted to god knows what else. Sadly the only way to break these patterns is to realize as soon as you are attracted to someone, it's likely they fit the profile of every other guy that has been in your life. If there is attraction you need to ignore it and somehow work through what makes you attracted to that type. Truely tragic. Keep that radar up and don't blame yourself for not trusting someone who has already shown plenty of reason not to be trusted.