New Rabbit

by RcX
(Texas)

Hey guys, I
I'm a new rabbit owner. I just got a pair of 3 month old Indian rabbits. Unfortunately, one didn't make it through the first night at my place. I now have one, but I was told bunnies should live with a bonded partner or in groups.

However, it's been close to a month since my bun has been solo. I'm always around him. Is this unhealthy though? Should I get another bunny or another pair for him?

I would also like help with understanding their behavior. Like, how do you know when they're happy/content, or feeling sick or in pain?
I noticed my previous bun laying on her side before she passed. I've begun noticing the bun I have now doing that too. It started about a week ago. Is he uncomfortable? Is there something I should look out for?

He's active and playful, and eats like he's supposed to.
Any suggestions would be appreciated. Thanks xx