all of us do stupid things, some of us, we try not to blame others for it. it is not that the other guy is not leaving you alone, teh truth is, you don't want to be leaved alone.

so, face it. you want to be with him, not the nice boyfriend.

do the right thing and break up with the boyfriend and please, don't try to do it nicely and stay friends. one sick-attachment at a time is more than enough

I agree, cutting someone off isn't hard to do if you want to do it. STOP talking to this other guy, do not answer his calls, texts, emails ect. if you do that for long enough he will go away. So quit playing the poor me card. If you can't stop talking to this other guy than your the jerk and your to blame not this other guy. and no its not that your a terrible girlfriend you are just selfish. Make a choice and stick to it, blaming another guy for your inability to stop thinking about him is lame. BTW from reading your question its VERY obvious that you like the attention you are getting from this other guy.

She DID pick and is trying to stay with the one she loves. And despite that she can't forget the other guy. This happens because we wonder what if... Just because you love someone doesn't mean you won't meet someone else that could possibly knock your socks off - or can forget someone who once did. Fact of life.

If you are confused and don't know WHO you love, you don't belong with any one but if you do, just go on and build a great life with the one you know you love. The rest is extraneous and will mess up what you have going if you let it happen...

I don't think she has picked... not conclusively anyway, she's still very much in a "haver her cake and eating it too" type of stage. On a conscious level she's definitely decided that the nice guy is the better match for her... but what she really wants is the not so nice guy who is chasing her. It makes sense, I guess - it makes her feel wanted and desirable to know that there is some guy out there who is going to keep trying to get her.

Of course I like the attention, that's what makes this so difficult, and screwed up. I wasn't trying to make it seem otherwise.
I actually haven't spoken to the other guy in months. When I say that I avoid him, I mean that I don't answer his calls, text, emails, videos ect... But they just keep coming.
I can't be with him, we literally aren't sane together. I don't want to be sucked into his delusions any more. It was completely disorienting being around him, and it was interfering with my life and work.
He consistently shows up to my favorite places, and I avoid them, or go at odd times, and try to ignore the fact that I hope he's there, even though I know that if I see him I'm leaving. We also frequent some of the same forums for specialized interests, and I refuse to engage in conversation with him there, but I don't want to have to leave either, I have other friendships that I have made through those. I know it might sound like stalker-ish behavior, but I can't make myself the the next steps, it would be hypocritical to get a restraining order or something.
I've made my decision, I'm with my boyfriend, but sometimes I get weak, and I watch one of the videos before I delete it, or hear his voice as I delete a voice mail, and I feel so disgusted with myself because I still find his voice intoxicating. I should be bothered by the fact that after months of silence he's still trying, that after I made it clear that we were done, that he's still trying, but instead I'm bothered by the fact that I love it, and then feel like the worst human being on the planet for loving it.
I don't want to give my boyfriend up, I worked to hard to be in a place where I felt like I could be with someone else, and I'm happy with him, something that I can't say about the other guy. And most of the time I don't think about the other guy, it's mostly when he sends me things on a special day or it seems like I keep dodging him one week that I start getting confused again.

You said that "you get weak" when it comes to him(the ex) and that you "still find his voice intoxicating." The only adjectives you've used to describe your current boyfriend are boring in comparison: "gentle soul" that's a "far better person than (you are)". You almost make him sound saintly in comparison to either you or your ex. You also said that you're happy with your current boyfriend, but have you been honest with yourself and with him -- do you really believe that you can be happy with someone who you don't seem to find exciting or intoxicating? For some reason, it seems like you find the exes dedication to pursuing you exciting and on some level even sexy. Here's a novel approach: why not try being alone -- completely by yourself for a while until you're better able to figure out what it is that you want in a partner? You owe it to yourself and to your current boyfriend to be honest and not string him along while you're sitting on the fence emotionally incapable of fully committing to the relationship you're currently in -- think about it-- what you're doing right now just isn't fair to him. On some level, you must realize that or you wouldn't be feeling so much guilt about harboring passion and other emotions for your relentless ex. Until you're capable of choosing one or the other, and committing to that person without regret or any type of lingering emotion for the one that you didn't choose, you're better off completely alone to give yourself the time and space to figure it all out. Good luck.