Is it normal to have feelings for a guy who treated you like dirt?

I became very close to one of my friends. We had worked together before and became friends. This past year I feel that we bonded, however nothing really could come out it because he had a girlfriend. But his girlfriend had taken the semester off. As the semester went on we became good friends and I did start to have feelings for him, although I never told him because he had a girlfriend and he really cared about her. Though he said they fought all the time and that she would get mad that he wouldn't text as much as she wanted. We went to eat all the time and we text each other all the time. One night I left work early and he called me on his break to see how I was and from listening to his voicemail I could tell he was concerned and that he cared about me. It was a few minutes until my birthday and he texted me saying that he was gonna wait until midnight but he was passing out and he wished me a Happy Birthday. I left my job but we still kept in touch by texting everyday. He asked why did I have to quit my job that he was gonna miss my company at work. When we got back from break, he told me that his girlfriend was mad at him and I asked why and he said that he had forgotten her birthday. He said that he remembered the date; he just forgot what day it was on, keep in mind that he remembered mine. So I got a job elsewhere on campus and at the end of the year there was a Christmas sale for all the employees only and they could bring one guest and of course I brought him. I even helped pick out his gift for his mother. On the car ride back he almost called me by his girlfriend's name and he said that he felt he could talk to me about his problems. We texted almost everyday on break and he told me that his mom liked gift that we picked out. We came back to school and it was only three days later he said that he broke up with his girlfriend, I was so surprised because the semester had only just started and she had only been in town for three days. He said he wasn't happy about it but he's confident he made the right decision. A month later, a girl that I was kinda friends with came up to me while at work and he came up right behind her and they made some funny comments about me and then walked away. I didn't think much by it until I went to his workplace afterwards and saw him and she was there and they was an awkward moment and then I went home. I got a text from him later saying that he asked that girl out on a date and wanted to know if that's gonna be weird because he said it felt weird when she and I were talking. I was HURT. I spent the entire night crying on my bathroom floor. I didn't respond to his text message. I didn't speak to him for a while after. I saw him at my workplace and he asked why I didn't respond to his texts, I knew it was wrong but I fibbed and told him my phone broke and I lost all my contacts. He said ok and that he would text me later, he didn't. We talked less and less after that. Though he hurt me, I still miss him.