Are you sure that the choice to ignore the injury is soley because of the bipolar? I am muchblike that as well. I tore my hamstring very badly in three places, at yoga non the less. I could feel the pain but I choose to ignore it as is usual for me and I also choose to keep pushing my body further. The torn muscles were cause over time from my hoicento ignore and keep pushing. I had sports physio and could not even extend my leg for a few mintgs making walking pretty difficult. The muscle had bleed all down the back of my leg, completely black before I acknowledged there was a problem. I have done this type of thing many times with injuries.

Anyways for myself that is not so much bipolar and more personality traits I have. That and bad self care (not wanting to see dr's) ignoring pain and signals from my body.

Just an idea on that that may or may not fit for you.