<human>: Could you distill the essence of the text into 1-3 sentences?

I've been in a relationship with this really great guy for about a month and a half now and I'm so afraid I'm going to fuck it up. I know that's not exactly a long time, but we have something very special and very different from what I'm used to. Everything about our relationship is otherwise fantastic, but it takes practically nothing for me to go from being super happy with him to feeling like he's slighted me or insulted me in some way. 

I become deflated and uncontrollably depressed and it's 99% of the time completely irrational. I find it extremely annoying and I hate myself for being this way. And trust me, when he's actually fucked up (which only truly happened once) I knew I was rightfully angry and offended and I knew the difference (and so did he and he apologized profusely). He's very empathetic and understands that my brain is constantly going and that I'm just over-thinking everything, but I'm afraid he'll reach his threshold with it someday. I need to figure out how to keep my emotions in check before that happens because he is the best thing that's ever happened to me.

The biggest reason behind my vacillating emotions is the fact that before him I've only been in terrible relationships and I'm always waiting for the other shoe to drop. He's basically perfect and everything I want in a person, but I can't seem to shake that mindset. I just want to allow myself to be happy and not try to subconsciously create problems that aren't there.

And also, maybe most importantly, I pride myself on being an intelligent, cool-headed, sophisticated woman and every time I pull an OAG move on him like this it's utterly mortifying.

Please help me, reddit.
<bot>: I'm overly emotional with my boyfriend, I become sad at the drop of a hat, and I need help on how to be a sane person with him so I don't fuck up this really great thing we have together.