First, are you in counseling or getting any help for your OCD? That should be your first priority.
Have you cut yourself or are all of these hypothetical situations?
1 and 2 - I'm answering these together because they are very similar.
If you don't see blood on the glass or table, there isn't blood. Most people wipe up blood from tables, etc., and however they clean it would kill the virus.
3 - A toothbrush can, in theory, spread hcv because if someone brushed their teeth and had bleeding gums, then someone else brushed their teeth and had bleeding gums, the first person's blood would have a point of entry into their blood stream. This is a theory, and probably not a real risk.
https://www.hepmag.com/article/starting-hepatitis-c-treatment-true-can-reinfect-toothbrush-dentures
It's never a good idea to share toothbrushes, what with colds and flus and such, but hcv is probably not a thing to worry about with toothbrushes.
Even medical personnel don't get hcv (or other blood borne pathogens, like HIV) at the rates you probably think they do. It's estimated that they have a 1.8% hcv infection rate following needle sticks. https://www.ncbi.nlm.nih.gov/books/NBK493147/
4 - Hairdressers sterilize all their equipment between customers, mostly for head lice and such, but it works for hcv, too, should anyone be cut.
HCV isn't that easy to get. You have to get enough of the virus from someone else's blood into your blood. Most new infections today are from sharing needles for drug use. If you aren't doing that, you really don't need to worry about it.
Please consider getting help for your OCD if you aren't already. Even though there is no cure, there is great treatment to help you manage it. (I say this with no judgement, only compassion.)