ray_zorse, I think this pretty sums up the biggest part of sexual mentality difference in genders.
Guys and girls are both humans with human emotions - both sides, after a break up are going to feel inclined to be sad, grieving, obsessed, low in energy and at a loss. In both cases, the solution to breaking the emotional cycle is to focus on other things (skills, missions, hobbies) and more importantly, meeting new partners, get some good sex and realize that there are other great people out there.
My understanding (so far) is that generally, a girl has more options than a guy does after coming directly out of a relationship - purely because of the fact that a guy must approach if he wants to retain his options, while a girl does not (again,
generally - I know there are always exceptions. I've experienced them.). Its probably almost always going to take relatively more work for a guy to get laid after coming fresh out of a relationship than a girl.
So yeah - unless the dude gets his off his ass and works HARD to get himself laid/focused on getting his shit together right after a break-up, he's probably going to feel like crap shortly thereafter when he realizes his seduction skills have atrophied while he was with his girlfriend, and that there's going to be hell to pay to make himself a desirable man again - while his ex is out getting male attention left, right and center to emotionally reassure her that actually, she's still just as attractive and desirable as before, and yes! Her boyfriends are totally right, her ex isn't worth the whiskey - and hey, look, this hot guy wants to take me home? Well, why the hell not, she's single now, isn't she?