Mbtexas, I know it seems like things are moving very slowly for you, but in most cases recovery for knee replacement surgery is easily 6 months and many times a year or more. So at 6 weeks, you do need to try and give things some time to level out.
Did you discuss therapy with your doctor? Having someone show you some specific exercises to do on your own might be helpful for both your physical and mental state.
If you are still having swelling and pain, be sure you are on scheduled pain medication and anti-inflammants (either prescription or over-the-counter). When I had my knee surgery, I took prescription pain meds for 7 weeks and then used Aleve daily for months. Like you, I had pain and swelling for quite a while.
I think you'll feel more like you're progressing if you can have a therapist's help in evaluating where you are, setting some goals, and showing you how to get there.