How do you keep from going stir crazy?

I am a FTM to a beautiful 3 week old. I am starting to go a bit stir crazy with being stuck inside all day. What are some things you do to keep from going stir crazy, especially when it is cold? I try and go for walks when its warm enough but the cold and snow seem to be sticking around.

Unfortunately, we don't live close to family so visiting for a couple hours is not possible. I also don't have any friends with kids who live close by and all of my other friends have full time jobs (I am very shy around new people so I do not have a lot of friends) . I need some adult interaction with people other than my husband.

I was fine the first two and half weeks at home but now I feel like the time is dragging and I'm just counting down the minutes until my husband gets home so I have an adult to talk to.