Depression anxiety. What should i do?

I am an introvert and always have been, 5 yrs back I changed myself and turned more confident etc and was very happy. Slowly, I had some issues with a few friends and relationship issue.(Also, I feel I am obsessed with marriage).I was an over caring and emotional person bt didn't show it to anyone. I have cried to sleep for months(3years back)because of hurting a person and was not able to overcome it. Because of the issues I again turned into more introvert. Becz of obsession,I keep thinking smethin bad will happen to me on my marriage day/aftr that. I read book secret that if u think smethin it will happen.I am not able to talk to anyone freely, and not able to focus on study at all.I keep thinking all day and night. I have recently recognised that I have minor anxiety issues, fear, slight obsession & depression.Hence,I am not able to talk.I did take medicine for a month and felt very light and happy but I felt that medications will make me addictive to medicines. What should I do ?