Heartbroken :( need advice plz?

I was in a friends with benefits relationship with this guy for about 5 months...at first it was just a regualr friendship i noticed him starring at me at work all the time then he just came up to me one day and introduced himself for awhile it was just like a hey and how are you doing type thing but we then started talking and we really connected and we still do but he always tells me he doesent want a relationship but he also has been sending me mixed signals all through these months too its wierd deep down i know he has feelings for me i can see it in his eyes and when i asked him he could not give me a straight answer.... we are platonic now but idk if i can be and it hurt soo much because i really care about him and i dont think i can see him with another girl idk what went wrong just because i had feelings he wants u to be platonic but he has always sent me mixed signal so i was never sure how he ever felt telling someone is one thing but showing it is whole another i dont see how he can just dettach himself from me like that i dont understand after all we went through what should i do