Okay, well, that royally fucked me over
Fuuuuvhhsjsjsj ╥﹏╥
Real talk.
This is not your casual yaoi story where abuse is overlooked and brusher aside.
I don't see Haesoo and Joowon ending up together. Mainly because of how unproblematic this author's former work is.
There is no way for them to "go back" or "start anew". Not after years of their abusive behaviour towards each other.
Haesoo has been trying to end things and not just for himself, but for both of them to get out of this cycle of abuse. He's tired of the pain they are causing each other and their parents. Joowon not being able to let him go (for now at least) is part of his need to control. The author does a great job of portraying someone who can't handle not being in control; not wanting anything to change, taking Haesoo for granted and expecting him to not want change either, getting angry over anything that isn't going "his way". Joowon needs this relationship to end. Otherwise he won't be able to get out of this abusive and controlling behaviour.
Taku is the catalyst Haesoo needed to end the relationship, and I believe Taku saying "You can use me if you want. Or rather, I'd prefer it that way" gave Haesoo the push he needed. And, as we saw in chapters 52&53, Taku is reevaluating his view on relationships and realising that he actually likes Haesoo. I can definitely see the "main issue" triangle drama shift to focus more on Haesoo and Taku's relationship in the near future. (Hopefully we get to see Haesoo and his mother trying to mend their broken relationship.)
I'm not sure I see anyone ending up together, they all have issues to deal with. But from reading Fools I would say it is more likely for Haesoo to end up with Taku, if anyone, and that would be after them actually talking about their insecurities and uncertainties in the relationship. (And they've been quite good at communicating already.)
Peace!
No what the fu ck