It's good that you reached out for help.
I'm also bipolar who takes 700 mg. Lithium, which helps lift the depression, and helps reduce the mania. I also take 7.5 mg. of Mirtazapine for depression.
You say, "I am marrying my fiancee in a week. He is diagnosed bipolar and is un-medicated"
I went for many years without meds when I was younger, 25-35 range, and had a job most of that time.
As I got older, say around 40, the mental illness increased, and I found it more difficult to keep a job, and in between jobs, the illness would be worse.
You said were depressed and might be bipolar. mayoclinic.org says sings of mania are:
Abnormally upbeat, jumpy or wired; Increased activity, energy or agitation; Exaggerated sense of well-being and self-confidence (euphoria); Decreased need for sleep; Unusual talkativeness
Racing thoughts; Distractibility; Poor decision-making — for example, going on buying sprees, taking sexual risks or making foolish investments
If you go in for a diagnosis, and you go in depressed, you may be diagnosed as depressed, and you could be bipolar.
There are many examples, and some on this forum from just the last 5 or 6 days, where patients are diagnosed as depressed, with no questions asked about, "Do you ever have racing thoughts?"
Meaning, you might be, as you say, bipolar, but the psychiatrist might not ask about that. If you're miss-diagnosed, you'll also be miss medicated, and you won't be getting any help.
I've just recently learned from the net, that if you diagnosed as depressed, you'll be given an anti-depressant, which could throw you into mania, and panic attacks.
Without the Lithium, or equivalent, to calm down the mania, you could have problems. I'm just saying, if you go in depressed, and you have a list of examples of mania, which you think you might have, I would show those examples to the psychiatrist.
I wouldn't assume the doctor is going to ask about if you have mania.
Your situation sounds like the one my now deceased wife and I entered into many year ago.
She had a mental illness and I did, too. We started out OK, but our illnesses did come into play and things got pretty rough.
One of my advices would be, I would be for holding off having a child right off the bat. I would give it as much time as you're able to see how this works. Living together can be tough enough, and with mental illnesses involved, it can be tougher than that.
It's good that you are seeking a support system. I didn't seek out something like this for many years, I didn't know there were such places.
I would urge you to stay positive. One saying that has helped me is, "One problem at a time, and be positive about that problem."