I like buying stuff as much as the next guy, but if not buying things you don't need would make you depressed, you probably have deeper issues that need addressing.
Do you know how many people pay the listing price of a car, yet cut coupons to save a few euros/dollars? A lot. It's ridiculous.
Some of the joys in life are simple things, such as drinking a $2-3 coffee or having a cocktail in a nice bar, etc.
The idea is that those small daily expenses tend to add up, and there may be a lot more of them than you realized.
"If you had stopped smoking 10 years ago you could afford to be driving around in a Ferrari right now."
"Do you smoke?"
"No."
"Then where's your Ferrari?"
Point is don't sweat the small things. Sure they add up, but you should dedicate a portion of your cash flow towards investments at the start of the pay cycle, not "what's left at the end." Then the rest can be spent on anything arbitrarily with a clear conscious.