JofME,
Family history of stroke can be frightening, and rightly so. With such a history, it's important to work with your doctor to manage modifiable risk factors such as diet, smoking, birth control pills, exercise, etc. High blood pressure is also a risk factor for stroke, so it needs to be managed.
It's doubtful that your family history of stroke is related to your Migraines, but you need to know that having Migraine with aura does increase your risk of stroke. The increased risk isn't anything to panic over, but certainly, you should discuss it with your doctor, and it makes it more important to control those risk factors that you can. For more informtion on Migraine and increased stroke risk, see Migraine with Aura Linked To Cardiovascular Disease in Women and Migraine and Stroke Risk.
I know how easy it is to feel as if you've tried everything out there, but there are so many medications that can be used for Migraine and headache prevention that it's literally impossible. You can find a list of potential Migraine and headache preventives in Migraine preventive medications - too many options to give up!
Be sure that the doctor who treats you for Migraines and the doctor who treats you for bipolar disorder work together. Some medications can be used to treat both.
If your doctor isn't able to help you, it may well be time to consult a Migraine and headache specialist. It's important to note that neurologists aren't necessarily Migraine and headache specialists. Take a look at the article Migraine and Headache Specialists - What's So Special? If you need help finding a Migraine specialist, check our listing of Patient Recommended Migraine and Headache Specialists.
I know you're going through a rough time. If you'd like some additional support, come join our discussion forum. You'll need to register again once there because it's a separate membership database, but you can use the same member name, email address, and password that you used here. You can find our forum at http://forums.healthcentral.com/discussion/migraine/forums.
Hope this helps,
Teri