Not with my pets, but when I tore a ligament it hurt like hell for 3
weeks and I didn't get full movement for over a month. It also re-tore
twice in rapid succession in the month following. I needed a brace to
have it heal. Then again, it was an ankle and I have to walk a lot.
All in all, it was 3 months healing time for me.

Always, when in doubt, ask your vet. IANAV.
/disclaimer

Definitely keep the vet advised on her status, but from what I've read it
usually takes several weeks for a dislocated hip to heal. It sounds as though
she's taking care of it well herself by limiting her activity. Since the
ligament may have been damaged there is a danger that the hip will become
dislocated again so it's important to keep her from moving around too much
until it heals. But it sounds as though she doesn't want to anyway.

Good luck and do check with your vet. He may want to see her again to make sure
it's healing.

snip for conciseness possible accident which may have caused the hip problem

Not my experience but others', from the web:

-----
"A veterinarian determined that Elf [the cat's] right hip had been dislocated
and it would take at least several weeks for it to heal."
http://www.debonosense.com/article_dc1.htm

"If it has been possible to manipulate the ball back into the socket your cat
will, in most cases, be prescribed a short course of painkillers to be
administered by mouth. In addition to this, your cat will have to be confined
indoors. This will usually involve either confining your cat to one room in the
house or in some cases confining your cat to a very small enclosed area such as
a large cage. Your cat will have to be confined in this way for around 3-4 weeks
before it is safe to let your cat venture outdoors again." But this may be for
only post-operative hip dislocation repairs. See more at
http://www.mypetspages.com/petinfo/feline/care%20of%20cats%20post%20hip%20dis.ph
p

From a 1993 Usenet Post:
"About 5 years ago one of our cats fell off the garage roof.  We found her
immoviable on the ground.   We rushed her to the vet and he gave us the "bad"
news, a dislocated hip.  He gave us 2 options: 1) Let her heal herself, or
2) Put her asleep.  Of course, we brought her home, gave her a comfortable bed
in the corner, food and litter box nearby.  Almost immediately she would drag
herself to the door to go out, but we didn't let her until she could walk
again.  Anyways, within about 6 months she was back outside running around
without any noticible limp.  Nature can perform some amazing feats."

From 2002:
"[The cat] got knocked down "again" last week been in the vets since, they put
his hip back in but its popped out again so they need to op on it"

From 1995:
"I woke up to my husband yelling that our cat was hit by a car and then spent
the next hour
finding a vet, finding a sitter, and mostly wringing my hands in the
vet's office while they worked on my kitty. We were very lucky that Turbo
didn't require surgery and that she managed to come away with only a
dislocated hip (which popped itself back in,) torn ligaments in her knee
and bruised hindquarters."

Also from 2002:
"One of our cats (we are owned by 2, both rescue-cats adopted as adults
from the local shelter) is an underfoot kind of gal.  Her favourite
way of getting in the way is to sprawl on the drive around the time DH
is coming home from work, forcing him to drive in slowly and
carefully, while she glares at him and f*i*n*a*l*y deigns to roll out
of the way when he gets close to her.

Last week, she didn't roll fast enough.  She has a dislocated hip and
some lacerations, but is healing nicely.  DH feels terribly guilty for
hurting her!  Hopefully, by the time she is allowed outside again (2
weeks in close confinement (our bedroom) a further 2 - 3 weeks
housebound before that happens) she will have learned her lesson."
-----

I'm  not a big believer in going to the vet's anytime something looks amiss, but
your cat's growling when she walks bothers me. Yet he does use the leg. This
would be a tough one for me. I think I myself would at least consider going to
another vet to get a second opinion and/or update. At a minimum, maybe some
painkillers would be in order (like the second site suggests). Maybe not, as
perhaps the pain helps keep the cat from overusing the leg? That's awful but it
might be the best solution. Also, I'm not sure I understand your post but I hope
you are limiting the cat's movements. Like some of the sites above say,
*absolutely* put her in small room with nothing to jump up on and warm low
pillows/blankets/towels/bedding, good food, her litter, etc. for comfort. If the
hip was dislocated but now is not, it could pop out again.

My cat had a limp around the age of two years once, but he was getting around
all right and there were no indications of serious pain (though surely he must
have had a bit of pain else why would he have been limping). The limping went
away within a week. My point is, they do often heal by themselves. Your cat's
injury clearly is much more serious, though.

I just googled for {cat "dislocated hip"} to come up with the first two sites.
There are others but these leapt out at me. Usenet seemed a little scarce of
good discussions on cat's dislocated hips, apart from what I cite above. But it
might be worth a second check.

Updates welcome.

I hope your little cat is better soon. :-(

I remember reading your original post and wondered if the hip was
x-rayed?  Dislocations and sprains can sometimes take longer to heal
than a break.  Also it can be the start of arthritis in the joint.  I
rescured a big white stray a number of years ago.  I did find its
owner and she told me Oliver had had a hip replacement!  Best of luck
to your kitty -- I hope she heals without any trouble.