With my first baby I stayed in my home except for Dr. appt's for about 4 months. I did not leave her with anyone, and I did not take her out anywhere. It was January in the upper penninsula of MI... I was afraid she would be too cold.
My Mom finally made me go out to eat for lunch with my hubby... and WOW, I needed it LOL Being a new mom, I was terrified that something would happen to her if I was not with her. Of course nothing happened, and she was fine.
With my 2nd baby, I had a 2 1/2 year old at home as well. I am a stay at home Mom, so I really really needed time for myself. As soon as my hubby got home we would eat dinner, then I would try to go hide somewhere just to be alone.
I did not have post partum depression, but I knew that I needed the time just to be ok (not crabby).
I think each person is different, and I know way too many Mom's that do not take care of themselves because they put their kids first. I think you need to take that time for you in order to be a good Mom and wife. How can you raise a happy family if you are not happy?
I would not worry about her, I think she needs time.