Message: Ok, so dont keep us in suspense, what is the name of the workshop you said you went to that so radically changed your photogaphy?As with many questions, there isn't a simple answer, but here's a list of the things that made a difference for me. You won't necessarily be able to do the same thing, but perhaps can find something similar.
1) In the 1970's I took a weekend photographic appreciation course at the Edmonton Art Gallery, given by Hubert Hohn. I thought it a complete waste of time and besides it was boring, but something took and within six months how I looked at photographs was changed fundamentally. I could appreciate a greater range of images and get more out of each image. The problem had been me, not the course.
2) Reading Fred Picker's "The Zone VI Workshop", a very modest book did more to improve the quality of my printing than dozens of previous books including all of Ansel Adams. Now, with digital and Photoshop, it doesn't have the impact it did, but perhaps there are modern books with equivalent impact.
3) Attending a Craig Richards and Keith Logan workshop in Canmore, Alberta - it was helpful and fun and we had some great photographing. It was the first time that I thought my work good enough to show, and was really the starting point for my writing and showing and selling. Some photographers have an inflated opinion of their work and none of us is a very good judge of our skills without getting some outside feedback. Over several workshops I came to realize that I was at least going in the right direction and might have something to offer.
In the 80's Bruce Barnbaum compared some of my prints to those of Jay Dusard - I was floating, then proceeded to point out a series of totally crap images (he was right). By the time I took a second workshop with Bruce and Tillman Crane in Nova Scotia a few years ago, I had a better sense of good images and the ratio of good images to bad was much healthier.
Feedback is essential and it can be hard to get objective feedback. Few workshop leaders are going to tell you your work is crap, but after a few workshops, you learn to read between the lines, and in looking at the work of all the other participants, develop a sense of where you are at. It's rather like reading modern report cards in which teachers are not allowed to say anything bad about a kid, but if you know the language, you can interpret. Making progress means you were lousy before and still have a long way to go. If the instructor starts talking about the quality of your mattes instead of your prints, you are really in trouble (or he is).
4) Getting published - it's a huge affirmation of one's work. Remember though that not all magazines or editors will like your kind of photography, or they may have published something similar recently so aren't likely to want more of same.I don't think contests are a good way to seek affirmation - unless you win of course.
5) Selling a print for real money. It's one thing to admire an image, another entirely to want it so badly you are willing to fork over cold hard cash. Selling to Aunt Mildred does not count however.
6) Compliments depend on who's giving them - kudos from people you respect, who have an artistic eye, or education or experience means so much more. The nature of the complement is important too. Good things said by someone who actually gets what you were trying to do, instead of simply saying they are lovely can be a big step.
In terms of how this information might help you. I can wholeheartedly recommend workshops by Bruce Barnbaum, (and Craig Richards if he is running any), or Tillman Crane or Michael Reichmann. Check around the net for other suggestions for workshops. I hear that Craig Tanner does fabulous workshops. He seems to have particular skill at improving your seeing and pushing your comfort zones in your photography.Your important milestones will be different from mine and trying to reproduce them may be pointless, but you will have them, especially if you make a point to get out there, ask questions, attend workshops, get help, beg favours. Serious photographers hate being asked to pat someone on the head, they generally love to talk about good photographs and most love looking at photographs if the person making them has put heart and soul into making them. Looking at image someone has made to please me is at best boring.