I don't understand why it was called "bullying herself" or "self-abuse". It sounds so strange. Is this a weird Chinese expression that doesn't translate well, or just a weird choice on the author's part?
I think it's a Chinese thing. Whenever it is a topic that would cause embarrassment (sex, masturbation, sexuality), they often dance around the words and never actually use them.
A Chinese webnovel I like (She Is The Protagonist - quite good btw) does the same thing. It uses phrases like "pleasures for adults" (sex), "breaching the gap to adulthood" (having sex for the first time), and similar phrases.
In manhua I've read, being queer is often rarely referred to as well. The common phrasing is "that way", like "I didn't know you were that way." or "She's that way."
Maybe a native or somebody more familiar with the culture can enlighten us as to why this is. My guess is that it has to do with politeness.