Am I depressed...?

I don't know how exactly a person should feel when he or she is depressed. And honestly speaking, I don't even understand what should I feel right now. The person whom I loved a lot is acting like a stranger just because I can't give him any commitments which he needs in his life " Why I can't give him any commitments? I can't because I don't believe in marriage. Since my childhood, I have seen couples having an unhealthy married life which has bothered me to the core of my heart and for which I started to hate the word marriage". I do respect his decision but what should I do now?

I know it's not easy for him as well but at least he has some wonderful people in his life with whom he can share his feelings what about me?

From the day I met him I always thought if he is with me I don't need anyone else and truly speaking before I didn't need anyone except for him because he used to understand me more than others.

Now I'm clueless. I am an introverted person in real. I can't be socially active with the people until they come to talk with me first. So, I think to share my thoughts my opinions my feelings. I have come here. Rest I don't know where my life will end up.

Sorry, I have written a lot, and thanks for reading so far. It means a lot.