Living with osteoarthritis does not automatically mean your life is over. There are ways to manage your discomfort so as not to impact your normal life greatly and also to slow down the progression of the disease.
Simple things like regular exercise, protecting the joints from further injury and maintaining an ideal weight can work wonders for you.
You need to maintain muscle strength as this takes some of the pressure off of the joints. A physiotherapist can help you decide what exercises will be most effective at building up muscle. An occupational therapist can help you figure out how to do the normal everyday things that may now be causing you discomfort like walking up stairs, getting into and out of a car etc.
You may be in pain and believe that exercise is not something you want to take up, you may be surprised at how effective it can be (in moderation) in improving the discomfort you are feeling. There does need to be a balance between rest and exercise.
Things like range of movement exercises should be done in order to relieve any stiffness you might feel. This involves taking your knee forwards and backwards through its normal full movement and then going a little further to give it a bit of a stretch. This should be smooth and gentle.
Strengthening exercises, as mentioned above are essential as well.
Hydrotherapy is another option for exercise; Gentle exercises are done in a warm water container. The water carries a lot of your weight so you are able to do more when immersed in water. Swimming is another great exercise.