Wow, I don't get the hate towards FMC because the MMC is the stupidest thing here. He's shallow, he is either dumb or blind to not see all the warning signs that blonde bimbo have when she suddenly appeared on their honeymoon and kissed him. Didn't deal with miss stalker properly either.
What I meant by shallow is that he only realised his "love" when he lost it. I gave him a chance in the early chapter since it is from the FMC's pov but then, we got his pov, I just knew he is the selfish jerk that suit miss stalker.
In the end, nice guys finish last. I just remembered the famous short comic where a dude healed a girl and she left with other man. There's no such thing as nice guy should be with nice girl. Meh. Life goes on I guess.