Need help staying motivated

Ok so league is a game and players are suppose to have fun. But when I find myself playing a roll I'm not to fond of I ruins the match for me and i loose interest. I can't stay motivated I'm easily distracted with anything and everything else. I tend to just watch the timer till 20 then spam surrender votes till the games over. I cant farm, watch my map like i should, or even help my teammates when they need me. I know i could play the rolls better if I'd pick a few champs for that roll and learned them its just the problem is none of the champs in those rolls are any fun imo. Their all just boring and i cant seem to play more then 3 games in a roll with them before I'm wanting to just play xbox or just anything that's not league. (I own all the champs btw) I just don't see the reason in maining any champ that i dont enjoy playing. Ya sure they maybe op at the time or just the counter pick to another champ on the other team, but fuck it if im not gonna have fun for the next 30-60 minutes. These rolls and mid sup and top. I can only play about 7% of ap mages and assassins if that. There's just no supports I find interesting and fun. And as for top there is very few champs i find fun to play and most of the time I'm stuck playing either the same one or none of them. Hell I don't even enjoy playing popular champs like Lee, Yas, Syndra, Elise... they just don't do it for me, and yet its debatable whether or not their a MUST to learn to play.

TL;DR Ok so I have trouble staying motivated and have a hard time caring about the match I'm in when I'm not having fun. So does any of you that has has this problem have any advise or tips that i could try to help me out or am i just fucked in those situations?