Um, if I wrote about myself experiencing depression on my essay, but I never seek for a therapist or doctor. Would college think that I lied?
It wouldn’t matter: there are so many mental health issues these days that it’d be a red flag. Avoid that topic. If it’s central, find a way to talk mostly about today, and not the depression.
No, they won’t think that you lied. Lots of people experience depression without seeking therapy. I assume that depression was germane to you in some manner and you felt the need to write about it. I think that’s fine as long as you show how you grew from having live through it.