Two wrongs don't make a right, the fact that Daichi knows that Shimada has feelings, dating or an exclusive boyfriend yet he still went after him is not right, but Shimada shouldn't have also revealed Daichi's feelings towards the manager.
I really hate this type of people who would do things or say things intentionally because they want to make the other person jealous, that's pretty toxic and immature in my opinion, honestly if someone said something like that even if it was a friend, I'd tell them to go ahead and get lost.
So I went back and re-read the other manga with their kids, in one of the chapters Daath will remember Julio nostalgically, so it made me think that something will happen between Julio and Will, or just Julio because Will is still friends with Daath.
I'm happy that more and more manga artists are talking about mental health.