As much as you love this guitar in every aspect except this, I would take it into a pro and demonstrate the problem to them and as what they can do.

Even if they have to replace the nut, it shouldn't be a huge deal. The nuts Gibson uses aren't anything to write home about anyway, so you could upgrade to a graptech or bone nut.

Given how much this guitar cost you, the cost of having this done would be nothing.

If it irritates you this much, you'll just never play the guitar.