I got confused, thinking there were missing chapters but the story progression really was that fast. It's a tad too fast for my liking, I would've liked to soak in that angst a little longer.
Yes it's an overdone plot point, yes it's cliche, yes he's a scumbag, yes she'll probably still forgive him, yes they'll probably end up together, yes his yearning and grovelling arc might be short
Im gonna sacrifice my first born child just so they get a happy ending