Has anyone overcome Existential OCD/Depersonalisation? (trigger warning)

Hi

I'm 19 years old and have been suffering from anxiety for perhaps my whole life. Throughout my teens I developed some further mental health problems such as depression. Due to a particularly bad bout of anxiety and depression I decided to take antidepressants again. My doctor told me Sertraline/Zoloft was good for anxiety so I started on it.

well I took the meds for three days but the side effects were too much to bare so I figured I wouldn't take them anymore and just do without. Three days after quitting I had a panic attack (I hadn't had a proper panic attack in over a year at that point) which seemed to cause my deprsonalisation. It's just been getting worse and worse since.

For three weeks now I've been getting these horrible obsessive thoughts and symptoms about these bizarre and deep philosophical questions and stuff. I keep asking things like 'what are thoughts?', 'what is consciousness?', 'how am I thinking?', 'how do thoughts and consciousness arise from brain activity?', 'is my entire life and reality and everything I think, know and feel all just down to chemical reactions?' And this sort of thing. These thoughts don't only terrify me but they also confuse and depress me. They've consumed my life. I can't genuinely enjoy anything because it all just seems to meaningless. Being 'alive' seems so strange. Just existing terrifies me. I'm actually afraid of my own consciousness and my own ability to 'make' thoughts. And a thousand other worries and obsessions like this.

I've tried listening to Dr Claire Weekes, it worked sort of initially but I've since relapsed. I don't feel real, I don't feel like 'myself'. I feel like I've forgotten what it's like to be 'myself'. I feel like I've seen a part of me and a part of something that I can't 'unsee'. I have no idea what to do about these thoughts about thoughts which terrify me. I feel like I'm going to be like this forever.

Can anyone relate? Has anyone overcome this sort of thing?