I think you're pushing her too much with taking treats from others at this stage. I'd get a treat bag and clip it to your waist and keep some high value treats in it. Several times through out the day when she is happy and relaxed, call her to you and reward her. Catch her "being good" (displaying happy relaxed behavior) and reward her for it. Do this several times a day for the next couple weeks.

Then when your friends over and call her to you, reward her as usual and let her go - she doesn't have to interact with others at all, just come to you for a treat and be released to do whatever she wants. You can even stand at the doorway so she doesn't even need to enter the room to get rewarded at first. You'll know she's ready to start interacting more with others when she starts choosing to hang out in the room with you and your friends and doesn't look for someplace to hide/need to be
coaxed out.

"During this time I basically ignored her until she reached out to me."

This is the approach you need to take with her around other people, too.