Wow I understand the pain that you feel and I am sorry that you are so down in the dumps. I think you provided another excellent reason on why Facebook, and social media for that matter, is a waste of time.

If you don't have any toxic relationships at the moment, good for you! But another way to re-evaluate prevailing toxicity is to look at your past and identify past negative influences or trauma and do anything in your power to dissociate from these experiences/people. If this is something you can relate to, may you always remember that you are not the same person as who you were, say 5-10 years ago to even yesterday. Even if you made mistakes that you currently regret now, making mistakes is part of human nature. I still have hope that you can re-discover yourself and you are not too late for anything, whether be it a new job, passion, etc. Don't give up! I believe in you.