I sell her what I have in my inventory and can't fit the basket. I guess she gives you what the would send to our bank account anyway? And I think she's adorable so yeah
Anything I can't be bothered to bring back, I'll sell. takes less time than releasing them one by one. It's also a decent gauge of pricing, if you can't remember what bugs are worth and don't have the Internet. Anything she'll buy over 80 bells should go home with you, or 100 if you're picky.
I usually only sell to her if I end up with extra bugs or items, and my storage basket is full. That way the extra bugs and junk aren't released and wasted, and I at least get a little from them.