I have being on the hiring side too, and if I asked you about that gap and got an honest reply about depression, that would tell me a lot. 1. you have identified an issue and worked to resolve it. 2. you are aware of it and may see it "coming" early next time (if it comes again).
I have been burnt too many times from people misrepresenting themselves in interviews (not being real to themselves to "sell" themselves) that I really value open and honest people. I think they know themselves, better, therefore their weaknesses and strengths too.
Could you hit rock bottom if I hired you? Sure, but it wouldn't be a complete surprise, and we could work together to prevent it and make sure you have the help needed before things got bad. (As if I hired you, it was for your skills and drive and fit and I'd want you to stick around to continue that).
Employers and employees can work though a lot if we both are honest and both are bringing something to the party (a job someone wants and the skill/desire to learn/perform).
Note I do not work in the US, and this is my experience.