Hi Heather,
Welcome to HW 
I can relate to almost everything that you said. My moods change rapidly too. Sometimes I'll have an episode last weeks, have had some last months (depression). But a lot of the time I'm all over the place. Mind you, I'm not on any bp meds. It's been almost a year since I went off the meds. It was a decision I made for myself b/c they all made my bipolar sypmtoms worse. I decided to focus on learning coping skills like CBT (cognitive behavioral therapy). I went into a support group, and I have done lots of reading. I also made a very scary decision this past January...
I too was in a very very stressful job. It got to the point that I knew if I didn't make a change, I was probably going to end up in the hospital. The illness was getting out of control. I left my job, went on unemployment from the goverment (for sick leave). Then I applied to the government for funding to go back to school to get trained for a new career. I will never go back to what I was working in. I am now starting school one week from today.
Managing this illness is about many different things. Making the right decisions for yourself, for your health, is number one. Therapy is key, glad you have that. Meds for a lot of people is necessary as well (it might be again for me someday). Having a good doctor/pdoc. Having some support (family and friends); sometimes that's hard...HW is a great support system.
You are doing the right things to accept your illness and to get better. It will all fall into place because you are making the efforts. I hope your depression lifts soon, and that you find the right meds. Keep posting, let us know how you're doing.