Dear Ava,

you’re welcome.

In case you know more about the topic, would you mind elaborating more on the topic of people changing personality during sex?

Unfortunately I don’t know much more, just that sex involves (or should involve) intimacy. If we’ve experienced wounding and abuse in our closest relationships, i.e. with our parents, the related hurt and the need to revenge and punish the perpetrators may come up during sex. Your girlfriend might have experienced some sort of abuse, possibly sexual, and her abusive behavior towards you is the result.

Since she wants to have (abusive) sex practically all the time, it means her personality is almost completely consumed by her shadow self. Even though you might have compassion for her, and seek to understand her better, try to remove yourself from the situation in which you are exploited, as Anita also suggested.