Welcome to the SR family!
I'm sorry your bf has chosen to pick up after staying clean. You have every reason to be concerned. It is a red flag in your relationship. However, the only person you can control is yourself. You are in control of how you respond to this situation.
He is an adult and has to make his own choices. He knows how to get help from recovery groups and/or therapy when he is ready. He may try to make you his recovery buddy, but that is not your responsibility.
My AXH came to me when he was ready to get sober, I pulled up the 12 step meeting schedule on my computer and left him alone with the information. He chose recovery. He asked me to help him with his recovery. I had to tell him that I could not be his recovery buddy, or sponsor. He needed to get support from someone that would call him out on his BS.
We are here to support you as you deal with the feelings and events that surround a loved ones addiction. I also recommend looking into local Alanon or NarAnon meetings. The only requirement for attendance is a loved ones addiction, even if they are no longer using.
Please keep reading and posting and let us know how we can help you.