I like your intention. I think using energy to dispel sadness in your life is really admirable.
The onlt caveat i have is this: to really cast effectively you have to have supreme confidence in what you ar doing. If someone is clinically depressed i think that may impact your ability to ground, visualize and gather the energy needed for what you are looking to do.
Thats not to say impossible...or improbable even depending on your knowledge and the amount of previous practice and experience you have.
Casting, as you know, isnt like taking a xanax or prozac...its not just words or movements, there is energy, intention and focus...and confidence.
If you come up with something please post your positive results.
Good luck. And for whatever its worth, there are alot of mundane ways to deal with sadness and depression without drugs; like exercise, diet and channeling energy into things you enjoy (art, games, whatever). But im guessing you probably have heard that before?