Rebirth of the Tyrant: Regent Prince is too Fierce

Why did the MC forget her memories? (To me it the same has forgetting about what the ML did to her in her past life and living happily with him, without knowing anything (I admit that I have watched to much manga to come up with something like this) If that is the case (in which I hope isn’t) living a second life was meaningless, it would just be better to be reborn in another world) 

https://www.kuaikanmanhua.com/web/topic/3365/
this one has a manhwa now 

This novel sound so complicated....I'm not even sure if I should read this. It's a good thing that before I started to read this novel, I went to check the spoilers first then decide whether to read or not. According to the spoilers above, I think the MC is a little dumb to not know how to change her life. She got 3 chances and nothing change....still going downhill. 

Can anyone spoiler about 1st life and second life. 

Thanks again for taking the time to explain it. It's a very good explanation, as the other one was, but I was half-asleep when I replied. I understand the alternate worlds explanation more now but it still makes my heart uncomfortable. I like the idea that true love is the same in every world. Since I'm the type of person that hates harems, even the alternate endings type. I will look for another novel then. No, I haven't read Chongfei Manual and don't plan to, knowing about that alternate version. Thanks for all the spoilers since it really helps people choose what to read based on their preferences. 

He's a maso..  

+ wants to know too 

After reading all this spoilers, I kinda agree about what you said regarding ML. MC was no one to him, so why should him protect her? Because she is MC? But he doesn’t know he will love her in the next life! The bitch helped him first and he is grateful, like, a lot of people say in this kind of novels “that ex-lover is ungrateful, she saved his life and helped him but he paid back killing her” but when ML is being grateful here, because is the bitch who helped him, people can’t stop themselves to criticize lol, sounds really hypocrite. I know that we will always be in the MC’s side. But what I said now is true. A lot of times we end up just seeing MC’s side and ignoring other people’s side, because, because she is MC! Anyway that is only my point of view.

But that doesn’t mean that this makes me more comfortable and to want read this story. I feel is too much drama and complication there and there, especially the crazy part.
And there is MC, reading the summaries, I thought, what was the reason for she even rebirth? For suffer more? If that is her/his ? goal then author made a good work lol
I should stop ranting >.<