Forced to say goodbye to her

I was forced by her to breakup and it hurt a lot she simply couldn’t do it anymore, as she viewed the relationship as toxic because she was bringing in all the abuse. The thing is she kept telling me she loved me so much and that she’ll never forget me when she was begging me to say goodbye to her, a day later she’s already on dating apps and thinking of the ex before me like I’m nothing. Is this common for them to just move on so suddenly? Is it a coping mechanism for validation? Since she cut off her main source and now is looking for love in other places