If your thoughts are induced by chemical imbalance due to depression or mental disorders, or if you have chronic pain, those are very challenging and no one can offer you help except professionals.
But if your thoughts are induced by life circumstances not related to health, for example your financial situation, family, toxic relationships, loneliness, etc. then life is definitely worth fighting for. Your problems will never go away, you can only hope to increase the quality of your problems, for example going from “I am starving and have nothing to eat”, to “I have my basic needs met but I have no friends” is already a big leap.
The real solution is having systems in place to handle different problems, for example handling conflict, social interactions, and even coping with unexpected loss. Life’s a bitch and always will be, but if you can develop these systems through experience, even if it takes years, and discover those small moments of bliss here and there that is what makes life beautiful.
Why switch if you don’t need to?