I have seen many people complain about this and I am sick and tired of it, solangelo is NOT rushed!! not at all!!!
there is a 6 months difference between BoO and ToA, which gives them time to get to know each other more. plus the 3 days in the infirmary. I highly doubt Will let go of Nico after those 3 days. I bet he checked up on him all the time, asked if he was ok, and made up plans for them to hangout together
also, I’m really sure Nico opened up to Will after a while about his past and how he struggled a lot. Will would comfort him no matter what, he’d try to make him smile and feel better so that he’s never upset. THIS WOULD MAKE NICO HAPPY. HE’D FINALLY UNDERSTAND THAT HE HAS SOMEONE HE CAN TRUST. SOMEONE HE CAN TURN TO WHENEVER HE’S UPSET
I don’t know what happens between the series either, but I can assure you that solangelo is NOT forced OR rushed