British number five Katie Swan says she was "afraid to embarrass" herself at the French Open before deciding to seek help for confidence issues.
Opening up about her struggles, the 20-year-old said she felt "less of a person" after every defeat.
Recently she started meeting a psychologist to "actively change and improve things".
"It has made a big difference to my overall wellbeing," Swan, who is ranked 208th in the world, said.
Swan was part of the Great Britain Fed Cup team which won promotion to the World Group II stage last month.
On her Wimbledon debut last year she memorably beat world number 36 Irina-Camelia Begu to reach the second round where she lost to another Romanian, Mihaela Buzarnescu.
On Friday she lost in the final qualifying round at the French Open after winning her opening two matches in Paris.
"Three weeks ago I wasn't sure I wanted to play in Roland Garros because I was afraid to embarrass myself," Swan, who reached a career-high rank of 163rd in October, said in a Twitter post.
"I'm heading back to London with my head held high and feeling very proud.
"This isn't something I'd normally open up about but it has made such a big difference to my overall well-being."
She added: "Now I realise that the life of a tennis player isn't about pleasing people or proving your worth to them.
"It's about proving it to yourself.
"If you can go to bed at night and tell yourself you are proud of yourself then that is all the reason you need to be happy and satisfied."
Swan said she has struggled with her confidence on and off court in the "last six to eight months" and decided to seek help a fortnight ago.
She hopes speaking out can encourage other people to seek help if they are struggling with mental health issues.
"Every match I lost I didn't just feel a worse tennis player, I also felt less of a person," she said.
"I decided to keep most of these thoughts to myself because I didn't want to be a burden for anyone and it is very hard to open up about this.
"However, a couple of weeks ago I thought to myself this could go one of two ways - I can keep feeling more and more down until I really can't take it anymore or I can actively try to change and improve things."