Cannot remain happy, dwelling in past.

Hi, it's been years now I just cannot be happy always dwelling in the past. I just cannot take dishonour, some one dishonoured me few days back in front of some people, it is still haunting me and making me more and more miserable. I cannot forget any bad experiences and it keeps on haunting me. When I am not happy, I make others miserable too, especially my mom and dad. I am a working professional and I just hate my job like anything, I used to prepare for government exams, but I have to leave it and start working in a private organisation. I cannot leave my job too as I am the only child and have to support my family. I am becoming more and more miserable as days are passing by, I request you to please suggest me some medications which can improve my condition and retain a healthy and happy life. I just cannot sleep too, and if some how I fall asleep, I just don't want to be awake or leave my bed thinking of the incidents. It's a humble humble request please help me out, please.