The First Boy I Told

Mark and I have gotten really close over the past weeks and are now in a steady relationship, just us two.
We had been doing very well but lately my emotions have been mean, and I shut him out on more than one occasion because of it. We argued a little about it, because he's genuinely good at communication and believes in talking things out, especially since he's still trying to understand me and how i work. The way he watches me is so hysterical sometimes because of that fact.
Anyways, last night I was out with Joseph and, Mark hadn't contacted me almost all day, and i imagined it was because of our argument about my pendulum-like emotions. So i sent him a quick text basically asking if he was still upset. He tossed his opinion at me, basically saying that he felt insanely disconnected from me when my emotions went haywire, and that he felt like it was becoming more consistent when I was with him, and he was starting to think i was semi-bipolar, and that that fact about me worried him. As he's had issues in his past with people with bipolar disorder, naturally he would be a little leery. But it pissed me off. I'm by no means bipolar, just lost and confused upon occasion.
Naturally, I told Joseph that I was going to Marks, and that I would be right back. Joseph and Mark live barely a mile apart so I told him I'd be there and back in a jiffy. So I raced angrily over there, walked in, and stood at the doorway to his room, where he was standing.
"Really?" I'd said, "you really think that about me?"
And he turned and looked, with this horribly distressed look on his face, and he sighed and said "yeah, sometimes." before sitting down.
He talked about it for a while, and said that he couldn't think of any reason why i would act this way unless i'd been physically abused, raped, or something like that. As it was technically neither of those things, I just sat and listened as he talked, very calmly, never raising his voice.
But as he started picking at some of the scabs on my heart, it got harder to fight back the tears, and I ended up standing in the doorway crying, looking away from him while I sniveled. He ended up standing up and putting his arms around me, muffling my silent sobs even more. He wondered out loud then if he even wanted to hear my story if it caused me that much pain to even think about. And I told him about my revelation a few days before.
He then pulled away from me, and invited me to sit down with him, where he cuddled and held me while I cried, then I started telling my story, not from the moment I met the bad 'B' word, but from the time he first took something from me. And he listened, giving his opinion a few times, but he was mostly quiet. And every now and then he'd put his head in his hands as he listened, as if it hurt him to hear it, as much as it hurt me to experience it.
In the end he thanked me for telling him my story, and told me that he equated what happened to me to be mental rape, and that it would all be okay, because he cared for me, and he was going to help me if and when he could. He was sincerely grateful that he was able to hear me tell someone for the first time in years, and be the first one of my boyfriends to hear, the first boy to hear.
I feel relieved now that he knows. Like i don't have to stand away from him, hiding behind a shield that he can't see. I feel like I don't ever have to let that series of events from years past ever hurt my new relationships ever again.