I have not read everyone's response, but in our world with our shy guy he too was a very reluctant walker. We tended to let him be the guide to where he would go, and we did a lot of just standing and taking-it-all in (a few steps out the front door). (after 8 years, we still have primarily 1 route that he will walk, while our other grey will walk anywhere)
He loved getting in the car so for MONTHS the routine became my driving my husband and the dog down the street (about 1/2 mile) and dropping them off on my way to work and they would walk back home... cause Kingsley was more-than-happy to walk back home.
Over time we would all get in the car, drive 1 block away and all walk around and then home... Kingsley has always done better walking with the entire pack (and one of our motivations for getting a 2nd dog)
I just recalled that he often would get over his anxiety about walking as soon as he was across the street, so we would carry him across the street, and then start the walk... oh, funny boy... lots of change over 8 years now.
So in some ways it will get better, and you will start to figure out when you can push it, and when you just need to let her stay in the yard. But as you can also see from our experience, it can take months and years and might not get to where you had imagined.