- tennis is not football
- you are lucky that you are playing superior players
- focus on improving one, or two max, areas only in every practice session
- focus on playing your best tennis and enjoying that, rather than only being able to enjoy winning (i.e. don't beat up on yourself)
- eventually you will get better and will win some game, sets and matches
Disclaimer: I'm NOT a coach...
Real tennis: https://www.youtube.com/watch?v=yDqnkLJ9BtM