OK first up I would see a different doctor one who is more knowledgeable about hep c and hep c transmission.
High viral load has no relationship to severity of illness.
Length of infection for those who have been infected for 20 years it is said there is about 20% chance they will develop cirrhosis. I was infected for 37 years I was diagnosed with cirrhosis after I was infected for 30 years but there are many people who were infected as long as me with no liver damage.
Hep c is not generally considered to be an STD by the CDC. In fact the CDC does not recommend barrier protection for long term monogamous couples. The is a small risk of sexual transmission which increases in the presence HIV or if you have multiple sex partners or engage in rough sexual practices.
So no you don't have to avoid sex but you may consider using barrier protection if it would make you feel better about having sex. There are many here who have been with a partner in a long term relationship and one partner has hep c while the other does not.
Avoiding alcohol would be a good idea especially until you find out if you have liver damage.
I have never seen anyone be told to avoid contact sports before. Just if you do get cut be careful around others and bandage your injuries.
Hepatitis C is usually spread when blood from a person infected with the Hepatitis C virus enters the body of someone who is not infected: Today, most people become infected with the Hepatitis C virus by sharing needles or other equipment to inject drugs. Before 1992, when widespread screening of the blood supply began in the United States, Hepatitis C was also commonly spread through blood transfusions and organ transplants.
People can become infected with the Hepatitis C virus during such activities as
Sharing needles, syringes, or other equipment to inject drugs
Needlestick injuries in health care settings
Being born to a mother who has Hepatitis C
Less commonly, a person can also get Hepatitis C virus infection through
Sharing personal care items that may have come in contact with another person’s blood, such as razors or toothbrushes
Having sexual contact with a person infected with the Hepatitis C virus
Yes I assure you that you will be ok there are new treatments approved in the last few years that have excellent cure rates. Your treatment could be as simple as 1 pill a day for as few as 8 or 12 weeks and you will be cured.
Here is a great set of articles about the Hepatitis C diagnosis and treatment journey from MedHelp.org. I hope it helps you!