I completely agree. Need more info on what the relationship was like before taking sides.

Completely true. But even then, he could've talked to her in person. I did it when breaking up with my abusive ex, even though it was difficult as ****.

Imo, the letter kinda points to him being an ass. He himself says OP was a great person and that he was the problem (not her). So based on his own words, plus that he paid for expensive flower delivery (feeling guilty?) it seems unlikely she was abusive, and more he's just too cowardly to break-up in person. I guess there's a possibility it was written sarcastically and that he spent all that money to...cause her to be disappointed??? But that just seems way less probable.

She could have reworded it

Perhaps, but the quotations seem to imply it was word-for-word, rather than heavily editted paraphrasing. In any case, I felt it was likely enough to vote FML rather than YDI, but I suppose there's always other possibilities.