Has anyone been in a situation?

Has anyone been in a situation similar to Jess and Dean from Gilmore girls? I can relate although I'm a women it happened at a workplace my ex started flirted with a co worker ignoring me he keeps asking why aren't we friends on Facebook. It's obvious he likes that co worker. It's been 3 years since we were laid off this morning he said on that co workers profile you know how I feel about you. I thought of adding him back on Facebook it's probably best if I keep him off. In a way I'm glad the workroom is closed it would be hard to deal with them still. I'm 33 my ex is 44 the old coworker is 24.