I'm working on a research, and I have a partner. We both should be working on the same tasks, but he's very busy, as he has teaching load and I don't, so I end up doing most of the work myself. This is not a big problem to me, but my advisor sometimes blames us for delayed results or little achievements, and I find it not fair to be blamed because he expects an outcome of two when there's actually only one working, and I get embarrassed to tell him that it was only me, because my partner is actually also my friend.
How does one deal with this situation? I know my partner is very capable, this is not an incompetence claim, it's just he has little time compared to me.