How Do You Stay Motivated or passing drug test?

So I was reading the boards on the RW Forums and someone posted a question: What is your greatest running accomplishment. For me, it would be completing my 10-mile race with a good finish. That race reminds me too of my initial goal which is to complete a half marathon (13.1) miles by the end of the year. I remember when I decided on that goal. Believe it or not, but it started as a New Year's Resolution. I wanted to start with a good plan though, so I spent a few weeks researching, and then I started my official "training" Feb 1st. I was SO motivated that first month that I refused to miss any of my planned runs. That actually may have been my downfall though. I was so adamant about not missing any runs, that I ran 3.1 in a terrible snow storm. The snow flying in my face wasn't bad, but the 5 inches of snow I had to run on was. The very next run is when my knees started hurting. I don't know if the two are related, but they certainly could be! In the past year I have successfully passed the drug test. Anyway, even with my knees hurting, I spent the next 4-5 weeks sticking as close to my training plan as possible. I had to nix all speedwork of course, and could only run minimal miles, but I incorporated more cross training to help compensate.

Well, fourteen weeks into my plan, I feel my motivation waning. I skipped my run yesterday simply because I was in a funk, and I didn't go running today because we had a long meeting after school and then I had to go straight to the Chiro. Tomorrow is Friday and I can NEVER run on Fridays. I'd rather run Saturday anyway. But still, that means that I will have only run twice this week! I remember looking forward to my running days and being all excited when school was over so I could go out on my run. I remember looking forward to my LSD runs on Saturday, really pushing myself to see how far I could go. Now...the love just ain't there. It may just be this week though. Things have been really stressful at work, so that could be taking a toll. Luckily the week is coming to an end. Maybe my Saturday run will revunate me. I hope so! I'm also thinking about finding a group to run with. There are two groups sponsored by different local running stores. I'll have to check them out to see if either would be a good fit. Any other ideas, maybe you know how to pass a drug test?

So my question to you...Do you ever feel like you just don't want to get out there (whether it's running or doing something else)? How do you find your mojo? Help me find that loving feeling!