
I bet the reason why they'll be together again is because of the car crash

Even if the car accident didn't happen they would eventually be back together. As you can see in ch93, haesoo is telling taku he's not sure he can't let that happen (cut out joowon from his life) that indeed he don't want that to happen, and that he has something to tell him (obviously to tell him the one month free trial is over) and taku knows it and interrupted him. Haesoo was going to finish what they had with tk sooner or later, as we can see here, sooner more than later. The car accident just made things go quicker.
They're both so cute together!!! Please kiss my babies!