It's absurd, but under law in England and Wales, it isnt "rape" unless it is P-in-V. Hence the Guardian's use of what would seem like a euphemism. It's only "rape" if it is a male who is the perpetrator.
I hate that she used a messy break up as an excuse to abuse these boys. A lot of people go through messy breakups all the time, and guess what they don't do.