So, I'm now down to option (a) or (c). I went for option (c). I feel like I gave the run a valiant effort. But, at this point, I was frustrated. Considering it's still raining three hours later as I'm typing this, (a) wasn't going to work either.
Instead of an 8-mile run, I did a 3-mile run. Not exactly the same. Now, I'm not sure what I do ... do I try to run 8 miles on Monday? I don't even know if I have the time to fit it in on a weekday. Do I want to run 8 miles Monday, and then do a speed workout on Tuesday? Is that too much? Do I need a rest day after a long run? Is it OK to miss that long of a run? Ahh! Pesky rain brought on all kinds of questions.