Katie, the recipe you're using looks dubious.
I think one of your problems is that you have been mistreating your yeast, which isn't uncommon. I agree with others that your water is probably too hot. Looking at the recipe, "the hottest that your tap gets" is bad advice. You're probably killing off most of the culture and it never really recovers once you do that.
I've developed a great relationship with yeast over the years (I have some fifteen or so different strains sitting in my fridge at any given time). The liquid you proof it in should not be "hot." "Noticeably warm to the touch" would be a better way to describe it, and no more than 105 degrees. I then add just a pinch of sugar and, despite what you will sometimes read,
I stir the yeast completely into the proofing liquid. Then just cover it loosely and let it sit for 20 minutes. If it sits any longer than 30 minutes or so, it will start to die off without food. If you do have to leave it longer than that, just add another pinch or two of sugar.
It's a myth that bread needs a warm place to rise. A little warmth will speed up the process, but it will rise perfectly fine at 68 degrees. It will simply take longer. I wouldn't recommend putting it in the oven. Again, you risk killing the yeast. Instead, you might just set the bowl on top of the warm oven, rather than in it.
I would also experiment with some different recipes. Even if a recipe claims to be a "copycat," it's only one person's opinion. That person could very well be wrong.