I was mislead into thinking the grass was greener - naive and stupid

I have been with my boyfriend for 2 years, a few months ago things were not good. For a while I felt very neglected; he would go out all the time, I felt his friends were prioritsed over me, I couldn't talk to him properly and it was very difficult. A college at work was persistent for my number and to talk to me but at first I said no. He would leave me gifts as a gesture and leave sweet messages. We got talking and we had a lot in common and I expressed my sadness about the current situation with my boyfriend. I felt as if he was being a genuinely good friend. We went for a drink and it was very platonic. We would have phone calls about general things and I felt I could really trust him as he was very kind and there was common ground. I then decided I didn't want this anymore and I wanted to sort it for good so he asked me to go to his to end whatever it was. He kissed me and I pushed him away. I feel completely repulsed and repelled by him and I feel stupid and naive to have been drawn into him - he insisted he wanted to be friends but he never wanted me as just a "friend". This situation has made me realise I actually love my boyfriend despite our problems. I have been honest about everything but yet I am still racked with guilt - I have been having panic attacks, horrible thoughts, I haven't been able to eat or sleep. I don't understand how my boyfriend could have forgiven me, I feel like I don't deserve him. I have asked if he wanted to break up but he said he didn't. I love him to pieces but I feel like he is worth so much more than me. I have never done anything this bad in my life and I don't quite know if I can cope.