How can i cope with the sadness at watching people living their lives while i do nothing?

Control: Seeing a therapist can help you in coping with it. You have to understand that you dont have control over other people and their lives. You can only control your own life. Its difficult to hear about other people and their negative life events, but their life is based on their own choices not the choices yo u make for them.

Comparisons: It sounds like you may be dealing with depression, and are comparing your life to others ("doing nothing" vs "living their lives.") this thought pattern will get you nowhere but further locked into envy, bitterness, and self-loathing -- none of which will improve life for you. Please tell your doctor about your state of mind & get help -- psychotherapy can be really useful. If needed, meds too.

DEPRESSION: Get an evaluation from a psychiatrist to help identify what depression means to you and whatever else may be bothering you. Consider recommendations for medication if any are given. Get a referral for a reputable psychotherapist to speak with. Meds and therapy combined are most optimal; no just one or the other.