My late partner & I were dating for about 6 months, when after dinner at his place one night he slipped away to his bedroom. He rushed back to the table where I still sat, literally fell to his knees, and nervously proposed to me with an engagement ring, totally surprising me just like in the movies! I accepted.
My present partner & I were also dating for about 6 months, when one day he casually said he thought I should move in with him. I agreed.
The very next day, while being introduced to a friend of his, he said I was his new partner! Hello! Men can be so silly, so different, so wonderful. We've been living together for 18 months now, as loving partners, all the legal documents between us drawn, everything but the marriage license our state prohibits us.
On the other hand... I dated another guy for about a year, and he had an absolute phobia about making any kind of commitment. I started to fall in love with him, but the only way I could keep him was if I pretended we were just casual friends. Even using the "L-word," as he put it, would upset him.
He insisted he wanted to play the field with other guys, which I accepted, and watched him make a mess of things every time. Then have him come back to me to help him sort things out, as his "only true friend in the world."
Men can also be so stupid, so predictable, so awful. LMAO!
Becoming "official" can happen over time without your knowing it, or it can happen in a flash. Whether you talk it over, send announcements to all the gay rags, or just realize one day it's already a done deal, there's no single formula for any 2 guys. Except I do think you'll know it when it happens.