Please help with support that I CAN say "I won't talk about the house right now." I just don't feel confident I have the right to say that, as it is co-owned.
Aver, Does BF know you want to buy the house? It is possible he'd be OK w you buying him out? Can you say to him, I really want to buy you out of the house, but I need some time to explore all my financial/legal options? Or don't tell him you want the house but you need some time to think this over and need to discuss with your financial advisor.
Your L should have better advice but it seems reasonable to me for you to tell him you need some time. And don't give him a deadline that you'll decide by. I made that mistake before. You are both 50/50 co owners, & after living there for how long, even if you didn't buy it you have to figure where you're going live. Again, see what the Ls say. The veterans should be by soon with better advice.