Be upfront or let it be?

So I went on a date with this guy in my grad school program in January. We have gotten really close and became good friends since, but there was the occasional sex involved. We are on break from school and I don’t know if I should tell him how I feel about him. I’ve never felt so comfortable with someone. It feels right to me but I also don’t think it is reciprocated to the extent that I feel. Do I let it be and let the universe do it’s job or should I be upfront and honest with him about my feelings for him. I need help, I’ve been toiling but I’m also nervous about losing him.