
I’m looking for a manga that was like this but the guy that breaks up with him to start a normal life have a kid. Then I think he breaks up with his wife or she passes away, and the lovers reunite and raise the kid....

I can think of these as the closest to your descriptions: Imaginary Lovers (closest to your description), Motoyan-papa to Hitsuji sensei (they were not ex-lovers but they reunited and raised the kid together - MY FAVE), Seishun Catharsis (not his own kid but his sister's kid).
Please tell me if none of these is right, I'll try to find another.

Literally after so many years, I’m glad I’ve finished it!! I do wish she built a different connection to Ryuu and chose him instead and maybe realized her feelings for him were different than the twins OR, out of the twins she realized she liked one more and would choose them in the end (I was rooting for emiya, but I felt like she got along with taihou more) but there were no such events were that really happens Bc the author is making it very friendshippy lmao but I’m still glad I got to finish it anyways. It’s still a cute story. Anyways BIGGGG thanks and Thank u so much uploaders and translators!! I only wish the same for the authors other work “teppen” which I don’t think is really finished.
OMG IAN T.T