How long have you had your mare for? A lot of what you describe can be put down to the stress of being in a new home (it can take at least 6 months for horses to settle into their new homes, some longer) and some of it can be put down to the way you are handling her and your relationship with each other.
Don't panic, I think a lot of people go through this with new horses. My mare was awful when I moved her to her new home, even though I'd spent a week with her in her old home and knew she was an angel to handle. On the first day she kicked my husband halfway across the field, attacked anyone who brought food into the field, wouldn't stand to be groomed, wouldn't lead, etc, etc. 6 months later I'd trust her with my 4 year old brother.
Anyway, you might want to stop riding her for a few weeks if it's getting to the point where you are scared of her. Go back to doing ground work - look up the parelli games, TTeam (my favourite), clicker training, etc and put one or all of them into practice (not at the same time obviously). Spend some time getting to know her without the pressure of getting on her back. And take as long as you both need (I didn't ride my horse for the first 2 months of owning her and it was well worth the wait).
Also, if the bucking and bolting persists, or she does it for other riders too, get the fit of her saddle checked, all other tack too. Might also be worth having the vet and dentist also giving her the once over (good idea to do anyway with winter coming up). If they rule out physical problems, a good instructor should be able to help with your under saddle problems.
Hang in there, it will get better. Also, if you want help on specific problems it might be a good idea to post them individually under the Training of the Horse forum. You'll probably get more responses.