The reason behind your depression is the Sun/Saturn 8th house. First of all, Saturn in the 8th is described as a scary placement, very scary. 8th house rules fear, and anxiety Saturn itself is the planet of fear in the house of demons and fears.
"[FONT="] So, Saturn in the 8th House people might not seem that overwhelmed with worry, at the outset. Sure, they may not always be “happy” but you can consider them fairly free of anxiety. That is, until you become intimate with them. Then, you meet a very different person who worries obsessively over all sorts of things that you’d never even think they worried about"
[/FONT][FONT="]"So, 8th House Saturn people can become bottomless pits of worry and fear, in this negative state, letting the feelings of doom cycle and cycle until they spin out of control. "
I recommend you to read this fantastic article about Saturn 8th house.
http://astroarena12.blogspot.com/2015/11/saturn-in-8th-house.html.
Important lesson is to learn to lose control over everything. You might come across as a stiff or controlled person that because you are controlling everything fearing something bad will happen.
[FONT="]Then you have Satu[FONT="]rn/Mercury in the 8th house that indicates speech problem, speaking anxiety, depression, [FONT="]academic achiever, sober mindset. [/FONT][/FONT][/FONT]
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