Welcome to the boat, only got the proper diagnosis for myself made this (wait, no, last) year, after over six years suffering with it. Still haven't found the proper medication combination for myself though.
No hypomanic/manic episodies actually put you in the recurring depression category, perhaps with seasonality involved. The DSM likes to over-complicate stuff, but pretty much bipolar I, bipolar II, recurring or seasonal depression and cyclothymia itself are all manifestations of one previous entity (pre DSM III stuff), the manic-depressive illness. Ye olde psychiatrist got that part right apparently.
Main importance on its diagnosis is the cyclical nature of episodes, family distribution, the presence of atypical symptoms and age of onset. If you consider this approach a lot of "major depressions" that DSM IV/V employ are actually manic-depressive illness, specially among young people. The concept is sound and in my practice I've had enough mishaps of not trusting the alert signs for MDI.
Medication ends up becoming essential to the disease as it's not just "sedatives" to avoid feeling stuff or getting manic, mood stabilizers are actually brain tissue-saving drugs as bipolar disorder causes long term brain tissue loss. Of course they are tricky to manage as they have side effects, weight gain, etc etc etc.
On the non pharmacological approach, best recommendations I can give is establishing a routine for sleep and other activities, mood is cyclical and is attached to the other cycles of our body, such as sleep and awake. So if you tune up one of them the others might get organized. Another psychotherapy also can help with dealing with outside stress factors.