Does anyone know the name of a manga where theres this guy who is 'dating' another guy but he treats him badly and claims that he doesn't really love him. Then one day the boytoy guy starts to stray towards a shy kid and then the first dude gets jealous and trys to win him back?

"Furueru Te no Saki" by Madarame Hiro?

Sounds a bit like Totally Captivated but probably not