The problem with me is that I applied to 4 programs and I didn't get in in any of them. The last program which was almost guaranteed admission (because I already found a researcher willing to accept me); I emailed my undergrad thesis supervisor for, what I called at the time of the email "my last reference letter request ever to make". Unfortunately, I wasn't accepted to the program and now I'm applying again to a different school.
The problem is I feel so weird about emailing him again for another reference letter. Other than the generic email, how can I go about emailing him? I am sure he remembers me , but I don't know how to justify the amount of requests that I've sent him so far !
Any idea on how I should approach the issue?