
How can you say you love him, but cheat on him with a girl, get this girl pregnant, and then say to his face that it was hard to choose between the two of them! Are you out of your mind!!!

It could be that the ring is a couples ring like Maya and Nemu in Hidoku.
Or to show he is engaged. He hid the relationship with the girl for 2 years. so maybe he has a commitment ring for two years but always took it off when meeting up with his gay lover.
I have an ex like this one. All I've to say is: thank god for the internet, especially when you cheat but you can't keep away from social media. A guy asked me out and I found through coincidence on facebook he's married and has one toddler! his pictures (even with the wife and child) showed him with no ring (either he disn't wear ribgs st all (allergies etc) or it makes it easier for him not having to remember when to put/take off the ring).
I imagine in pre internet days it's harder to find out.

Because Love has nothing to do with Carnal Pleasures. He could have love him, but he wasn't satisfied sexually so he had to look for other people. I am not defending cheating, but you see this in the real world people who do love will try to find someone else because their not 100% satisfied.
Wasn't expecting that, XD