Facebook is SUCH a mixed "blessing" (?)
If you believe what you see, everybody except you is having a wonderful time, exotic holidays, meals out (or delicious morsels prepared by a partner or paragon child) getting a new car, puppy, or child/grandchild.
I would add it can be isolating in itself. If nobody "likes" a comment you have made, you can feel ignored and spurned even by your nearest and dearest. It frequently relays too much information and leads to people feeling sidelined or plain left out.
Been there, shed the tears.
On the other hand it can span thousands of miles, keeping you in touch with people that you might not otherwise be in contact with, can give the odd laugh and if like me you are partial to cute kitten or dog videos it can be great.
Just remind yourself, nobody posts on Facebook that they are lonely, bored, can't afford to put the heating on and only have toast for tea. Nobody posts that they have not spoken to a living soul in a week or that their joints ache so much they can barely drag themselves down the garden.
Maybe if we did, someone out there might recognise a cry for help.