I'm pretty certain I have a shopping addiction. I am house bound due to disability and unfortunately most days coming down stairs and seeing i have a package is my highlight and brings some happiness but its getting out of hand
I can understand wanting something to brighten your day, could you maybe make something, are you crafty? Then you could sell via etsy and maybe that would help you find a way to spark some joy in your life.
Why do you think it is getting out of hand? Are you spending too much or have too many things? Also, maybe you can spend some of your time rearranging your things, turning some things into projects, selling things you no longer want or donating old things. This is what I do and it helps me stay busy sometimes. This said, there is nothing wrong with feeling happy when you see a package but try to balance it out with some of the ideas above.