Full history: After finishing For Auld Langs Syne I returned to the Lucky 38 to pickup a replacement for Arcade Gannon, who is now with the remnants (which is also broken, hes a shimmering blue guy in the enclave base; and lame, he should be available to continue in my party in his Tesla armor after the quest). I decided it was time to work on Boon's quest. When I clicked on Boon he got upset that I was working with Caesar and I reassured him that it wouldn't happen again (I am accepted by Caesar but certainly not siding with him, I'm doing an independent Vegas, w/o Mr. House).
I believe something happened to Boons autofollow script after he chewed me out for working with Caesar, causing it to open dialog every time he stops moving while following me. Hes completely unusable now because of this.