Both men and women are susceptible to it.
Something starts going good, you get scared, and you look for a way to mess it up. This can happen consciously or subconsciously, though usually it's sub.
"It's just too good to be true."
That statement is a statement of self-sabotage.
Stop it. Enjoy when things are going well. Life brings enough problems, don't add on to them by wrecking what's good.