Hi! I totally understand your concern for your health and its obvious that you are suffering a lot. To comment, whether it is a bipolar disorder
or not, we need to have a detailed history of you and the same is lacking in the information given by you. We agree that there was a significant stress in your childhood, but the same can predispose you to depression, PTSD as well as anxiety disorder. Although you are taking "Valium" its more of a cosmetic relief and you may land up with benzodiazepine
dependence and hence it will be always wise to start you on some form of SSRi medications. The other best option will be to consider psychotherapy
and cognitive behavioural therapy. basically you need to see a psychiatrist
for a detailed history and evaluation , who would like to run a few psychological tests on you, before he starts you on either psychotherapy or pharmacotherapy
I hope this answers your concern.