Sorry for the long post, but I feel as if I have to give the full story to be fair to myself and my boyfriend.

I had just gotten out of a 5-year relationship (my ex just came out of the blue and broke things off and then started dating a mutual friend a month later). I was hurting and had very low less esteem and self worth after the break-up. I befriended a guy I had met at the dog park. We were friends, hanging out and texting. I didn't want a relationship 1. Because I was not ready for one 2. He was a lot older than me, as in, old enough to be my dad.
One night after hanging out, he kissed me and it started from there and we ended up having sex. I would have never initiated sex with him, but when he initiated it, I didn't stop it and went along with it. It felt weird because I did not have romantic feelings for him nor did I think about him physically. However, when he started kissing me, I went along with it. I'm still not completely sure why I went along with it, but I was hurting and had felt unwanted by my ex, so it felt good to be desired and wanted by someone.
We continued to hang out and ended up having sex again.
I felt dirty and ashamed of the fact that not only was I in a friends-with-benefits relationship, which was very out of character for me because I had only had sex with two other people, both of which were long term boyfriends, but also because he was almost twice my age. I told him I no longer wanted to continue our relationship and he seemed ok with it.
This happened over the summer.
In the fall, I met my current boyfriend at the dog park. We hit it off right away. After several more dates we started to open up about our past sexual partners. I told him I had been with 3 people and told him about my five year relationship. I did not mention my most recent partner, or his age because I am embarrassed about it and I didn't want it to ruin our budding relationship. I told my boyfriend I had had a one night stand and made it seem as if the guy were my age. I lied to him, plain and simple.
After dating for a couple months, my boyfriend and I went to the dog park and he was there. I went over and said hi to him. I knew he had seen me and he knew I had seen him. I didn't want to ignore him and be rude, so that's why I felt I needed to respectfully say hi up him.
When we got home from the dog park, I came clean to my boyfriend and told him who the man I said hi to was. As expected, he didn't take it well. He was, understanibly, upset with me for lying and also for me going over to him to say hi.
My boyfriend had a MUCH harder time with it than I could have ever imagined. He started drinking a lot and when I'd come home from work, many times he'd be drunk and angry. We did a lot of fighting and I apologized and promised him I'd never lie to him again....which I have kept.
During an argument, he kept prying into what sex with guy was like...and because I promised I wouldn't lie to him no matter what, he asked if the guy was bigger than he was. I said yes. I also told him that size doesn't matter to and that I love having sex with him and don't desire anyone else. He continued to pry and pry, asking me repeatedly if bigger felt better. Again, I promised to be honest with him and I answered yes, but that there is so much more than just size that makes sex what it is. I also told him how I felt when I was having with him and that I was having the best sex I've ever had.
He says that it's impossible to be having the best sex ever if he is smaller than my previous partner and the only reason I enjoy sex with him is for the emotional connection.
Things between us got really bad. He would drink and yell at me and call me several things and told me I'm a size queen and a slut. We didn't talk for a week and he apologized for the emotional abuse and he agreed to stop drinking in excess and drinking alone.
Months have gone by and though he isn't drinking like he was, he is still having a really hard time with the fact that "bigger feels better." He says because of the fact I had a relationship with someone based solely on sex and the fact that it was with someone almost twice my age, that I disgust him. I remind him of the several one night stands he had before we knew each other, but he says they were years ago and he wants to be with someone who wouldn't do something like that.
He is depressed and tells me he thinks about his "small ****" constantly and feels emasculated and can't enjoy sex anymore and that I ruined sex for him. I continue to share how I feel about him and continue to apologize for lying and got my past. I do not think my boyfriend has a small penis and I want to have sex with him all the time. Despite all I tell him, he either finds a way to negate everything I say or just says he doesn't believe me. He tells me he hates himself and can't stand the fact that someone felt better than he does. He says everything else about our relationship is great except for sex because of what I told him.
I love him very much and I know he loves me. We have both made mistakes. My concern is that it has been months and I feel that it has only gotten worse.
Please tell me what you think about all of this, and please don't hold back. I know I some really bad things.

Thank you.