One of my professors told me to write my own letter. I thought it would be cookie cutter at best (since I had to write things about myself). She emailed me the letter to see if it was okay. Then I find out, that she made a few modification and I was shocked at how good it was (she ranked me in the top 5% of students she ever taught!). It really changed my opinion on writing my own letter of rec...
Well anyway, write one up anyway. She maybe more including to spiff up your [do it yourself] letter or rec. and made it golden!