Some have advised to just smack the woman. However, you can’t force feelings on someone.
The bottom line is that the best advice to ignore the competition no matter how much the woman casually mentions them or rubs it in your face and just focus on being super-awesome. Go work out, get sexy with the woman – because at some core level, she still wants you, get better clothes, get a good haircut, and especially do what the woman wants in bed as much as you can.
Anyway, this might not work in the heat of a post-breakup or something similar. Experts advise leaving because the heat is too hot.