I don’t feel like i’m healing

it’s been a 16 days since me and my now ex boyfriend broke up and I thought I was healing and getting better but today has just been really hard and I can’t even put a finger on why. I just really miss him. and to make it even worse I was scrolling through my snapchat stories and i’m still friends with his friends and they posted a video of him on their story and he seemed happy and better off without me. we didn’t end on bad terms, and he still wanted to be friends, but I told him I needed space. and now idk how to rekindle that friendship. I just hate that we act like strangers now. it hurts.