It’s super late right now so I apologise in advance for any typos and if my post doesn’t make much sense. But I just wanted to say a big well done to you for taking time out to get yourself into a better mental space (even if the decision to drop out and work on yourself wasn’t entirely your own), and that*I’m really glad you are doing so much better.
I know you might feel like you are behind right now but trust me, your mental health is more important that anything else and if you needed time out to deal with things, it was the right thing to do and not something to be disappointed about. Would you really want your life to still be what it was a year ago?
The exams and exam results will come - you are clearly an intelligent and self-motivated individual and I have no doubt that you will get the grades you need to get into university. I would imagine what with what you have been through, you will have sufficient grounds to apply with extenuating circumstances with the highers that you have, and if not, there will be other options to get in (gap year to sit an extra higher, foundation courses etc.). *I wonder if you have spoken to a careers advisor about your options?
Please don’t give yourself a hard time for what you have been through. *Be proud of yourself for how far you have come and believe in yourself.