I struggle with this too. Perspective is really what helps me. Any amount of money that you make can be high or low relative to who you are surrounding yourself with. Try volunteering at a homeless shelter or getting involved with Habitat for Humanity or something. It's hard to feel bad about your salary when you work with people that just want a bowl of soup. On the contrary, if you hang around with a more affluent group than yourself, you may be more likely to feel like you are not making enough. Take a look at mean/median salaries in your area [1]. You are doing fine!
[1]: https://en.wikipedia.org/wiki/Household_income_in_the_United...