Does anyone else think Riley is one of the worst character's on the show?
No, he wasn't one of the worst. He was THE worst, by far.
I'd rather listen to S5 Dawn screeching "Get out get out get out!" a hundred times than watch Riley mope even for a moment.
Do people just hate Riley because he's not an undead/broody/sexy vampire?
Not at all, and I'm actually pretty sick of that argument as well, "You only hate him because he's not a vampire and he's normal!"
Nope, sorry, there's "normal" and then there's "Riley." The two aren't synonymous.
He is believable in his needy, whiny, selfish ways because thats what love does to a person.
Okay, and Angel was believable in his consuming, passionate love for Buffy, the "first love" love and all. And Parker was believable in his total college-jerkiness. And Spike was believable too - his obsession of wanting to kill Buffy transforming into an obsession of wanting Buffy...every character in the Buffyverse is believable in some way. But they aren't all whiny, complainy, insecure, and boring as Riley is. I don't care if he was a REAL person. They all behaved as REAL people, even the demons most of the time, and they weren't all as annoying as Riley!
Buffy did treat him like crap. It's her attitude that provokes such a response from him
Okay, I'm not saying Buffy was a saint to him, but I hated him long before his "responses" (I'm assuming you're talking primarily about his behavior in S5).
I hate him in S4. I hate everything about him. His corniness, his "Look at me! Look how wholesome I am!" attitude, his contrived lines (WHAT were the writers thinking?! The writers are usually brilliant at dialogue, but it's like they had a monkey write Riley's lines..a dumb monkey at that..), his ridiculously irritating insecurities ("My girlfriend's stronger than me! Waaahh!"), his selfishness ("My girlfriend won't put out while her mom's dying! WAAHH!"), his completely unreasonable jealousies ("WAHH! MY GIRLFRIEND HAD SEX WITH A GUY, ONCE, YEARS BEFORE SHE EVEN KNEW ME! WWWAAAHHH!!")...man, I'm getting angry just listing it all, and I haven't even talked about his stupid haircut yet..
Basically, Riley's actions S5 (the vamp whore business especially) and his boringness factor only a little bit in why I hate him. It was what he DID, not what he didn't do, and who he WAS, not who he wasn't, that made me hate him.