I think therapy is more than just the 50 minutes I spend with my therapist. I sincerely try to invest some real time into thinking/writing/otherwise expressing my feelings and thoughts about what we've discussed each week, and that work takes me to what I want to bring into the next session. If I want a vacation from therapy, I take a week off and skip a session.

Of course, there are some weeks I avoid thinking about any of it--and those weeks, I admit, make for less useful sessions. But it is up to me--it's my choice whether I do the work between sessions. My therapist will be there no matter what, but as he's said to me repeatedly, it's entirely up to me whether I make progress. So there's nothing wrong with taking an easy week--as long as I get back into the fray the next week.