My (recent) ex-gf may have dumped me for a disturbing reason

Hello,
I'll try to keep this as short as possible.

My girlfriend dumped me, after we had been together for seven weeks. She called me, we talked like we normally did, then she just said that she is busy next semester, and said she'd have to break it off.

I was pretty upset, nothing too major though, but I knew that that exchange should have gone differently. Mostly I was just confused.

I decided to focus on the fact that she was busy, which she probably knew about for two years. Because of that, I wrote a very unambiguously-phrased letter, where I, in a calm manner, explained that we couldn't still be friends, since the entire time we were together, she must have been planning on dumping me while I was away for the winter, and that she probably used me as a self-esteem booster.

I read that letter after writing it, and decided that sending that to her would be really immature. I messaged her, and said that I wrote her a letter that she wouldn't like, so I wouldn't send it, and that I would rather talk in person than throw around accusations.

She politely wrote that she was too busy to talk in person any time soon, and asked for the letter anyway. That caught me off guard, so I guess my mind went into autopilot, and I disobeyed my initial gut feelings and sent her the letter. Predictably, she wrote me a letter back, and just denied everything. I remember thinking it was interesting that she wrote me a response two hours after reading my letter, rather taking a few days to ask herself if perhaps she subconsciously did what I accused her of, or rather than telling herself "hmmm, I've only been in one relationship (not this one) that was longer than a couple weeks, and this guy thinks I manipulated him, so perhaps he may have a point."

Last night, it occurred to me that I had it all wrong. Rather than focusing on the reason she gave for dumping me, I should have focused on how she did it. For example, she didn't say "hey, I'll be busy, so our relationship might be in for a rough time. I want you to write down ten things we can do to help the relationship, and I'll do the same. When I pick you up at the airport in less than a week, We'll compare notes and see what we can do."

Instead, we talked normally for five minutes, then she practically blurted out that it wouldn't work out because she's busy, and broke it off.

I got to thinking about how her trying to exercise control, or make a decision that involved me, without wanting my input, basically screamed "defense mechanism from a traumatizing event." Then I concluded that she told me "this won't work out because I'm busy," because she was afraid I would eventually tell her "this won't work out because you're busy."

There's one thing that I sort-of used to double-check my math on this, so to speak. Remember when I said that she was only in one relationship that lasted longer than a few weeks? Well, that one lasted two years, and it was a rough breakup on her, and she dumped him a few months before her and I got together. And well, she dumped him because he was too busy.

So I guess that in conclusion, it's my honest belief that she dumped me because she was afraid I'd do to her, the same thing that she did to her previous boyfriend.

She doesn't want to be friends anymore, but I feel the responsibility to tell her that I misinterpreted the evidence, and shouldn't have sent her any accusing letters (and I didn't want to, but she requested it), then tell her why she really dumped me.

Am I flattering myself, and is my interpretation of why she really dumped me just a bunch of weird/paranoid speculation, or could I actually be right?

Thanks for your time.

Hi, Funkmaster_A! It does sound like she might have broken up with you because that relationship was painful for her. You could apologise for that letter and tell her what you think happened or ask her if she thinks this might have happened.
You're right, though, the way she ended it was insensitive.