Could someone explain this to me please ┗( T﹏T )┛

Here's how the timeline goes:

18 years old - Oikawa and Iwaizumi start dating.

20 years old - They break up for a while, and Iwaizumi gets a girlfriend.

2 months later - Oikawa is in the hospital for anorexia and an ulcer.

1 month later - They get back together.

2-8 years later - They get engaged.

Iwaizumi broke up with Oikawa because he thought he was taking "his happy future" (a.k.a. kids + wife) from him, he tries to get over oikawa and fails miserably meanwhile oikawa can't handle being away from hajime so he takes little care of his health which result of him getting anorexia + an ulcer. Iwaizumi realizes in the hospital that he almost lost oikawa and even if he doesnt know if they are gonna last and that tooru can change his mind anytime (in the previous dj he tells oikawa that is alright if he wants to break up with him) he still wants to try and have a happy ending together

Thank you so much ε=ε=(ノ≧∇≦)ノ