My Dad's life centered around my mother for the almost 65 years they were married. He had lots of hobbies, but when it came to socializing, he basically followed my mom's lead.

After Mom passed away, we worried a bit about Dad because we were afraid he was lonely. Well, he was . . . for Mom. But as we talked to him we discovered he was perfectly fine not socializing; that was Mom's thing but it wasn't vital to him. He wasn't unhappy or even particularly lonely without socializing; he just missed Mom.

Your dad likes to be with your mom and follow her lead; that's okay; that's how they roll.

But finding your own time with your parents is kind and I'm sure your dad will enjoy it. Just don't try to "fix" him. He sounds like he's just trying to be thoughtful and considerate that activities are inclusive of everyone who might be interested.