I hate myself right now and I don't know what to do

This is going to be a long one so please bear with me. I'm 19 and have been in a relationship with my current girlfriend, Viki, for nearly two years. And I really believe I was/am in love with her. But back in December, I started getting to know this girl Kim, who works with my best friend. And now Kim and I have developed feelings for each other and it's causing a lot of problems. Some background on Viki: we met during my senior year of high school when I moved to a new town. She was a freshman, and from the first moment I saw her I thought she was cute and pretty. I was the new girl in school, and she wasn't out, i don't even think she was out to herself. So it took awhile before we actually got together. there was a point when I thought she wasn't going to pick me and I hated myself for liking her soo much. part of why I didn't ask her out was because family is very important to her and she had great relationships with her parents and didn't want to lie to them about dating me, so we were gonna wait til she came out. that didn't happen. However, about a month and a half after we started going out, she did come out. and we were forbidden from seeing each other up until last month. But, we've been in a bit of a rough patch since like november, when her sister attempted suicide. Now KIm, I first met her about 3 years ago. I had gone into my local iparty looking for who knows what. buuuttttt, there was this girl there with a f*ckin awesome mohawk,. and god, i thought she was cute. last year, I went to iparty in search of her for advice about my mohawk. I know i could have gone to a hairstylist, but she was a chick I knew who'd had a mohawk soo.. and then my friend got a job at iparty this year. and he became friends with her. MIke would tell me how alike Kim and I were. We both love kids, love English, we have soooo much in common. and the first time we actually hung out, we ended up talking almost the whole time. And we hit it off sooo well. We immediately got along. and sudden'y. we were crushing on one another. actually, she developed an interest in me before we even hung out. from all the stories mike told her about me. She was actually bummed to find out I have a girlfriend. And we started hanging out everyday. just before new years, she had a party. just her, her friend, mike, one other girl, and myself. We both only had a few beers, me because I feel awkward drinking other peoples' booze, and her so that she wouldn't do something stupid. that night, because there weren't enough couches downstairs at her parents house, I went up to her apartment with her (nobody was going home because there was a snowstorm). we ended up talking and i asked what was on her mind. She said that she wanted nothing more than to kiss me, because she really liked me. So i told her the truth, that I liked her too, but that I could never leave Viki. So we tried to just be friends. But we always found ourselves flirting and acting like a couple. and now... now we're not on speaking terms. It's gotten too hard for her to be around me since I'm not picking her.

Hi LUCET, Always be positive, never be angry at yourself. Try to see the good side in all and remember you`re young, enjoy life and always tell the truth because you`re a good person and people always like good persons. Even if you upset someone now on the long term that person will see you as a truly good friend. Weigh your words before you speak them in front of someone and become the best of you. Follow your heart, be polite and smile.