Speaking from experience, it does to some extent. Salary as a geologist in hydrocarbon exploration is pretty good so I could afford to do it, if I wasn't earning the salary I was then it definitely would have backfired. You have to have a lot of disposable income.
That being said, it got me out of the house, wearing proper clothes, and made me interact with people outside the house. Wanting to go shopping to buy things
helped me tackle insomnia because I finally had a purpose for leaving the house (I had a lot of time off in between rotations). Wearing the nice things made me feel more attractive which is the biggest player in self-confidence for someone who used to be a little self-involved. Retail therapy can help alleviate symptoms, but as a guy above said it doesn't help with the underlying causes. If it is a chemical deficiency then anti-depressants like SSRIs can be lifesavers (as they were in my case), or it could be psychological only in which case therapy is usually very effective. Don't rely on symptom relieving methods, speak to your doctor asap, don't let it build up and control you. Good luck and if you need any extra help pm me.