I feel like this accident is on me for not having moved to the right sooner. 

If you pulled over too close to another vehicle, you could have caused a collision with them. If you sped up more, you would have increased the risk to yourself. You're not obligated to make unsafe maneuvers because of someone behind you.

140 is too fast though, especially in winter. For your own safety, slow down and use the other lanes and leave other people to put themselves at risk going 140+. I know it's popular opinion that going way over the limit is fine, but you're significantly increasing the risk to yourself if anything goes wrong. Excessive speed is consistently the biggest killer on our highways.