It's exactly the same thing that happens to me, my last years in high school were very difficult. I missed all school trips to keep people away from entering my life.
I just can't reciprocate when someone smiles at me. I feel like a part of me just stopped working. I see people being happy and enjoying life with others and I can not understand how they do it without getting bored.
"sometimes I'm ignoring them for no reason" me too, I have some relatives who care about me and always try to take me to different places, but lately I'm not even going out with them.
When I was younger, I had many dreams and plans for my life, but now I do not even plan my weekend. I've lost my will to get into a relationship, my best friend has a crush on me, but I just do not reciprocate even wanting, I see her almost every day in my dreams.
Every attempt to improve I lose more will and motivation taking more than twice the time to motivate me again. It took me five days to get myself motivated to write those sentences.
I created the courage to talk to someone about it. She listened to me and gave me some recommendations to improve my quality of life.
So i will start a supplementation with 5 htp and L-tyrosine to improve my mood and motivation. I really hope this works.