Hi there and thanks for the post.
Sorry for the delay but the other ideas put out there are great.
A few short things. I wouldn't recommend dragging her to the dog park as this will not help. I use the green room to explain this.
Imagine you are scared of spiders and so they decide to put you in a room. The room is green and has a basketball and rubbish bin in it. Then the room floods with spiders.
You freak out and get really scared. At the end of it you are still scared of spiders....but also green rooms, rubbish bins and basketballs. This is the problem with flooding.
So instead continue with the ignoring the fearful behaviour and reinforcing the confident behaviour as you have been doing. But the idea is to start slowly reintroducing things.
You may have missed things as a pup but you can follow the same way now.
Start with simple things like in your backyard with a dog at a far distance. Fear gets ignored ie no eye contact, no petting, and no praising. And when she is confident praise her quietly to build up her confidence
Once she is happy in this situation keep on extending things to other situations. Do one thing at a time to avoid flooding her and always give her a way out if things get too much.
Medication may be helpful to help her get over that first period. I prefer Clomicalm but talk to your vet about what they think will be the best thing to help take the edge off.
Be patient, avoid flooding her and give her time. It may be a good idea to let someone else socialise her a bit first as she may not be as fearful without you for a while
Just give it a go if it doesn't work don't carry on with that.
Let me know how things go and keep up the ideas out there guys it is always helpful.
Todd