I hate writing synopses, too, and I used to do them very badly, which didn't help matters, either. Then a friend of mine pointed out that I was getting too bogged down with the play-by-play and that's not what agents/editors are looking for anyway, especially in an initial contact/pitch.
The key points the editors look for are character set-up, emotional (or dramatic) turning points, and resolution. If you just focus on getting across those 3 elements of the story, you're set. The blow-by-blow description isn't necessary.
Once I understood that, I could write a synopsis quickly and basically off the top of my head (without having to go back and wade through the manuscript page by page).
Now, this only holds true for a brief synopsis -- a lengthier one by its very nature is going to require more play-by-play -- but now I don't dread writing synopses and the ones I write are a lot livelier to read. Think more "back of book blurb" and less "roman numeral outline of plot".
Hope this helps,
Jennifer