I have these episodes of what I call depression frequently. For a week, sometimes two, every month. I feel lonely, extremely sad, isolated, unmotivated, and just tired all day. I'm at the edge of tears most of the day. I tend to isolate myself because I feel that no one wants anything to do with me. I have a small circle of friends and lots of... suitors, for the lack of a better term, so I guess I have people to occupy my time.
I haven't been to a therapist or anything because I'm embarrassed.
I know everyone experiences different things, but I'm just curious to know, am I just feeling lonely, or is this what depression feels like?

I'm not asking for a diagnosis or anything. I guess what I'm wondering is, what is depression like for you?