first of all, yes, I'm just writing anonymously due to the nature of my request. I've been an active member of this site for many years and I appreciate and value the people here.
I don't really know what's wrong with me. I get depression attacks every once in a while and there's no apparent reason for it - it builds up during the day or the morning and by the afternoon or evening, I feel extremely distressed, anxious, I doubt everything, can't focus on something educational, things I enjoy would only distress me even more (such as loud sudden noises/laughter in the TV shows I like, or sound effects from games) so I can't use them to distract myself and I begin to look for indicators that my social environment falls apart. I lock myself in my room, make everything dark, and would stare at a random page on the internet without browsing it or just lie in my bed.
It feels like an extremely sudden and deep experienced loneliness, despair, sadness. Usually this lasts for the rest of the day and sometimes for the day after.
I'm aware that this is something I believe my mind is making up, because there's no tangible reason for these feelings, I'm living a good life. I do have academic stress, but who doesn't? There are some fights in my family, but nothing really out of the ordinary. I am not socially isolated. In short, I don't know why this happens, and neither did the therapist who I consulted years ago - so I stopped seeing him when he would just start to ask me "What do you want me to do for you exactly?" every time.
Since these "attacks" only occur from time to time (rarely in the past few months, but frequently the months before, around 1x per week), I wouldn't call it an ongoing depression. However, due to the inexplicable nature of the despair, I feel like calling it a sad day is an understatement.
Maybe someone can share some advice on what to do in such a situation. I don't feel like calling one of those help hotlines, they make me feel like I am suicidal and I am not. I also don't want to occupy the line for people who are and seek help.