Hi @Green_Swan firstly, congradulations for nearly reaching your graduation. It is such a milestone in your life and definitely something to be proud of. I also want to thank you for speaking out about the way you're feeling. I can imagine so many more people feel like this yet it isn't a common thing to talk about.
I also want to mention that I feel quite similar at the moment. I graduate University at the end of this year and I'm nervous and scared for what the future holds and what I am going to be doing.
Do you have any particular interests that you could see yourself going further with? From what I've read, you're going to be graduating from high school (correct me if I'm wrong), so that could be the first step in determining if you want to further your education through going to Uni or TAFE.
Feeling like a burden on your family is also something I can relate with. About a year ago, I made the decision to end my studying this year with an undergrad and not go onto do postgrad. My parents were supportive but still questioned me and asked what I would be doing for a job instead, and when I couldn't give them a clear answer, there was definitely tension. My decision to not go on to do postgrad was mainly due to burnout that I constantly feel, so if that is something that you also suffer with, do not feel like you need to jump straight into uni or a full time job.
It's also good to hear that you're doing things to combat these feelings, exercise is definitely a good way to clear your mind from things that may be worrying you. I'd also recommend, if you're comfortable with it, write down how you're feeling when these thoughts happen and also speaking about it to trusted friends, family, or even reaching out to a professional (such as Beyond Blue; https://www.beyondblue.org.au/).
Here is an article I found on 'Graduation Anxiety', it is American, but it definitely sheds a light on what you may be feeling and how to deal with these thoughts; https://embracingyoutherapy.com/feeling-anxious-about-graduating-3-ways-to-manage-post-graduation-an...
I hope this helps in some way, and remember that you are not alone in feeling this way 😊
