Have you tried using a crochet hook to grab the dropped st? For k st use it from the front, purl from the back.
Another option, which I have used on more than one occasion--and believe me, its legal--is to just kind of weave the dropped st in. If you've been able to continue the pattern w/o that st, then just kind of secure it to the back. If I realize that I dropped a st because I'm at a place in the pattern that I need it, if I can't bring it up with a crochet hook and have it be unnoticable, I secure the dropped one and add a st where I need it. Even though I have lots of experience, stuff happens. In the end, I'm the ONLY one who knows where these oopsies are. If they are too noticable, then yes, I frog, and have done that alot. But not if I can fudge.
Knitting should be fun and relaxing--not raise your BP!