Urgent. Friend crisis. Heart crisis.?

I like my bestfriends ex. SO lets jus nick name him y. And lets nickname my bhestfriend a. SO a and y went out in the beggining of 8th grade year. we're freshman and y's a sophmore. well i talked to y all summer long and we bonded on a whole nother level. Just recetly he told meh that he was stuck between two girls. Those two girls happened to be me, and his curent gf. not a. Hes not even thinking about a. ANd its really hard for me to find boys that i like. so im wondering if i should just take the chance and go with it or not. help???