I am a mental health nurse, and this is what I have come to believe: A bit of history...after (currently) working five years in level one psych (highest acuity in this state/locked unit/independently standing, so no in-house medical resources, etc...) night shift charge nurse position; & four years booking assignments through a nursing agency, working in dual-diagnosis/straight substance dependency/corrections facilities primarily.
You're own experiences will ABSOLUTELY serve to make you a better, more empathetic and more SYMPATHETIC nurse, certainly. You will have a unique "insiders" view to some aspect of everything you see in those patients who share your diagnosis, and thar can be wonderful for the patient.
I don't believe it is necessarily ethical for you to share your history with acutely ill clients IN YOUR PLACE OF EMPLOY. Others will no doubt disagree, but I feel that it puts you at risk for legal action (sadly, in this day and age, psychiatric clients often are looking for an "edge", an "in" on the mental health employee caring for them. I could elaborate and certainly will if you like, but for the moment, I'll leave you with this...
IF you choose psychiatric nursing as your specialty, and you want patients to know you "get them"/their histories/etc...do so by sharing that you have a choose family member with their diagnosis. Explain that you understand through living that person that, "X, Y, & Z can be very challenging aspects of living with bipolar disorder...". It achieves the same goal you are looking to achieve, but does not compromise you legally or ethically.
Finally, if you really think about it, you will come to the conclusion that you CAN PROVIDE the very same ethically empathetic, sympathetic, and EXCELLENT care without that client ever knowing your history at all...and that, honestly, us what nursing is all about...THEM. Not you at all! Just some ideas to mull over.
Very best of luck to you. Again if you are interested, I'd definitely like to post OR PM you with some other info about the choices you are considering! Let me know! :0)