ive noticed alot of people saying lily was bad and a beast and stuff like that 4 leaving sev. Why do (if u do) u think that?

For me, it's because she was able to forgive James, who, for the entire time she'd known him, had been nothing but a bully to Severus and everyone around him. It says in OotP (I can't think of the exact place, but it's in the chapter where Harry sneaks into Unbridge's office) that James jinked everyone just for fun.

At that point, the only thing that Severus had done was call her a "mudblood" which he apologized profusely for, and hung out with people who she thought were "evil."

If she could forgive James for tormenting her best friend for years, why couldn't she have forgiven Severus?

There's also the fact that she dated (and married) the man who tormented and humiliated her best friend for so long.

She wasn't a bitch, 'kay? Just an unfortunate series of misunderstandings that led to what happened, along with Sev's alignment with the wrong side.

Well, he did not act like a jerk like James. And Lily was more important than anyhing to him. And out of no where she just decided James seemed mature and Left Sev broken. ):

I don't think that. Here's what I think happened. Lily was, quite obviously, angry. When Sev came to apologise, she hadn't cooled down yet, and was still to angry to accept. (How many people you know have accepted an apology when they are in a temper? And the book did say Lily had quite a temper) Later, she probably didn't want to think about it and/or was too shy to aproach Sev after that. Another possibility (that I tend to think is what happened, but that is just my oppinion) is that she loved him too (without realizing it) and he broke her heart when he called her a mudblood, and she was afraid he would do it again if she went back to him. Just my opinion.

i dont think lily meant to hurt serverus

I think Lily chose to let Severus suffer. first, by refusing to forgive him after she saw that he was truly sorry and then by dating and later marrying his worst rival.