You may need to crack one of the connections on your water meter to drain the water down lower than you hosebib.
Either that, or saw it off and let it drain that way.
Or open the wall behind it, and work at it from that side. Either way, if there is water in the line, no amount of heating will melt the solder.
Frankly, I always cut the pipe first.
After it has been drained down, and then preped, only then do I consider putting a torch on it, and that's just to solder it back up.
You old hosebib will never drain down from the hose side.