Your so right to get to the Doctor and catch it early.
I had life long Depression before my proper diagnosis Margie, as well as UCTD, one step down from Lupus) and Fibromyalgia and I spiralled into a mini breakdown after the Copd diagnosis.
Like you, it was a nurse that triggered it, by acting so shocked that I'd gone from mild to moderate in 6 months. She scared the living daylight out of me.
It may help if you also ask for a bit of counselling. I won't go into detail as I've posted so often about it on here.
Five years later and it's still my other conditions that are causing me the most problems.
Some of us go into a deep grieving process, imagining our lives are over. But, I've learned from this site and many others that that isn't the case and life expectancy is pretty much the same as for everyone else, but the quality, depending on how well we look after ourselves, is the major concern.
I know you won't believe me but, this depression can be beaten but, not without help.
I think having other debilitating conditions, makes our reaction to the diagnosis, harder to come to terms with. But, it can be done and I'm proof of it. xx