Draw a line between thinking of you own self and worrying about a particular person. What must have been your priority.  You have a bigger responsibility of your own growth for which you need to aspire on success,  set appropriate goals both in personal and professional life. Next is to look at the causes why you have been thinking negative about that particular person??  Analyse if you had some bitter experiences in the past. If so, work on letting it go and move ahead.  Consulting a Counselling Psychologist will help you to channelise these things. You seem to be emotionally connecting to that particular person.

Hello . You need to focus on your aspirations and your goals in life now at this age . Don’t waste your time thinking too much about people . Plan your life. People will come your way , good and bad . If you are strong and focussed nothing or nobody will harm you . Think positive and be positive.

HELLO Please take homeopathy flower remedy and do yoga meditation Thanks