I bought the pamphlet The Cautious Canine, it has a lot of great things in it. It help to understand the dog and how they react to their own fears.

Have your boyfriend be the #1 provider for the dogs needs; feeding, treats, walks.. etc. EVERYTHING!!! Also have him ignore the dog, like Tanya said, let the dog approach him at her own pace.
It took Buddy 9 months before he would take a treat out of my hubbies hand. Not even a huge chunk of steak would get Buddy to come near him.
I find now that if my hubby is laying on the floor (the leat threating posture) Buddy will come right up to him and let Rick pet him, no closer than an outstreached arm's lenght. But still.. he'll come up to him.
But if Rick moves the slightest bit, Buddy will dart away as far as he can, taking out anyone and anything in his path.
Tell your boyfriend to be cautious if/when he tries to give her treats from his hand, Rick has gotten his fingers Chomped on a few times by Buddy!!
It's a little safer to put the treat in the palm of his hand.
Now that we've gotten a little further with Buddy, Rick is finally able to put a collar and leash on him (it too 2 years for this to happen) Rick and Buddy go for walks/runs together. He'll also put him on a leash and just walk him around the house. Twice now while Rick's had Buddy on a leash in the hose Rick made to sudden of a move that Buddy wasn't expecting and Buddy has pooped himself!
I wouldn't try that just yet with your boyfriend and dog... that's further down the road.
As far as London staying in the bedroom and not comming out, don't let London go IN the bedroom. Close the door and don't give him a place to run to. I did that for a long time with Buddy, he would stay in another room (peaking around the corner keeping an eye on where Rick is at all times) And I would let him do that. Once we met with the behaviorists, they said to block off the room you all are in, and don't let him run away. I did this by using a gate to block off our living room. He would lay right by the gate, but at least he was in the same room with us!
Again, I HIGHLY recomend you 3 meeting with a behaviorist!!
It was the best thing I did!