By no means give up hope. Many of the people on Floridaratlist , Ratlist and other forums have tamed totally wild rats, in short, by lots of experimentation in communicating with them in the way RATS understand. (I know it is a cliche you hear over and over in every animal book and movie -but its true you have to "think like a rat" NOT a human). Millions of dollars are invested in training rats to detect bombs by the military. Nothing is impossible if you commit yourself to it. I have over 200 videos I made last year (some on Youtube) when deciding to tame a wild rat, but I don't have the bandwidth to upload them here.
Whatever the method you choose, I can't emphasize enough, but set up your technique to allow the animal to chose for itself, without coercion or force, and you can never go wrong. The overall 'theme' should be to "give a rat what a RAT needs." NOT what a horse, lion or parakeet needs (sorry, I am a horse trainer), but a rat is a prey AND predator animal.
Step 1 is to keep the rat alone until her panic response is under control. She insisted on biting me, so instead of force - handling her, I left the cage on my bed where she could (theoretically) get used to my scent and come / go at will. 100% of the time she ran straight for the edge and dived off like a maniac ... unlike our domestic rats, who will strive for the highest point in the room.
Here is where creativity comes in (there is not a set rule for every rat) . I borrowed a dozen small buckets of water and lined up around the bed. After diving into the "moat" three times she effectively NEVER jumped off again.
Step 2 was to teach her that "my shoulder" was good. I filled up the bathtub and allowed her to make the choice: 2 times 'accidentally' diving into the bathtub, and she regarded my shoulder as a place of security. She 'got" it!
#3!!! ....What is the one thing every living thing wants ('cept maybe a hamster)? Companionship, of course!
Now it was time to turn her loose on the bed. Of course she wouldn't jump off (knowing she'd meet a tub of evil water!), but her new MO was to run under my leg and hid for security. Poor little thing, from having run loose and alone from a baby, she was just terrified of the world! Once under my leg (she decided I was the safest place to be), she let me touch her, flip her, weird stuff like cartwheel her and do anything to her.
The 4th step (6 weeks later) was to bond her with another female. Due to her lack of ratty social skills (a separate challenge) she was extremely aggressive to the newcomer, but I was able to mitigate that with more training (squirt bottle), and throwing them into new (and scary) adventures together.
I have males, and unable to keep any girls, but finally adopted them to a 1st time rat owner with NO complaints. I had NO interest in trying to change "Pineapple." Her anxiety and social fear were #1 priority so I only focused on that -reducing her anxiety . Once a rat, or any animal, associates that "you are good," she will let you do anything with her ... I clipped her claws weekly, and bathed her 2-3x/week. I held her upside down, and she bruxed and didn't move, because she now associated me with safety.
In conclusion, where there's a will there's a way! The only thing that concerns me is the pregnancy biting. It's completely common, and under no circumstances means she will continue when the babes are weaned. Been there done that. Its just hormones. They will abate after birth and weaning. Feel free to pm and leave your # if you would like to talk ok anytime
She is in desperate need of a bath cause she is covered in only god knows what but she is rex so her hair I know is supposed to feel a bit wirey? 
