Wow, you are like super considerate to this Chuck guy. From the perspective of Chuck I would have to say that you are the best friend ever. However from your side--do you know how heartbroken Chuck is over this whole thing? Like would he be really pissed off if you dated her, or if he saw her with you all the time?
Other than that in my humble opinion/experience, I think you shouldn't worry about Chuck THAT much. I do really appreciate the fact that you are an awesome friend though, far better than I ever would be!
EDIT: Yeah also as Bernard Black said--you should at least hear her side of the story and like, what's going on. Even if you just remain friends it's going to be hard to juggle the two, at least that's been my experience.
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