Get in good shape, if you’re not already. “I’ll show you what I’m capable of. I’m going to find someone better.” That kind of deal. It works. That’s what I did when what I believed to be the love of my life (she called me her soul mate!) up and married some German douche. While still claiming she loved me, to boot. Better to not focus on people like that, at all, but that’s not always realistic. So if you must feel pain from it, why not decide to make it the pain of self-improvement?