Would you keep giving this company your business after this?

[sourwolf]

How would you have handled that situation? Was it an overreaction on my part to leave and never go back?

To answer your questions:
I would not have "engaged the crazy." Specifically, you said:

She continued on, saying crazier and more hateful things, so I finally said "Excuse me, but I'm trying to hear this."

I would not have said anything. I would either ignore the woman, get up to use the restroom, or step outside.

Yes, this.  Just because someone is talking doesn't mean you have to respond to them.  Especially when they are saying crazy things. 

[Luci45]

How would you have handled that situation? Was it an overreaction on my part to leave and never go back?

To answer your questions:
I would not have "engaged the crazy." Specifically, you said:

She continued on, saying crazier and more hateful things, so I finally said "Excuse me, but I'm trying to hear this."

I would not have said anything. I would either ignore the woman, get up to use the restroom, or step outside.

Yes, this.  Just because someone is talking doesn't mean you have to respond to them.  Especially when they are saying crazy things.

With someone like that, I think I would have been afraid to corner myself in the restroom! If she was escalating, I shudder to think how far she may have gone! Probably not, but caution is a good thing.

[sourwolf]

How would you have handled that situation? Was it an overreaction on my part to leave and never go back?

To answer your questions:
I would not have "engaged the crazy." Specifically, you said:

She continued on, saying crazier and more hateful things, so I finally said "Excuse me, but I'm trying to hear this."

I would not have said anything. I would either ignore the woman, get up to use the restroom, or step outside.

Yes, this.  Just because someone is talking doesn't mean you have to respond to them.  Especially when they are saying crazy things.

With someone like that, I think I would have been afraid to corner myself in the restroom! If she was escalating, I shudder to think how far she may have gone! Probably not, but caution is a good thing.

If the OP hadn't said anything the crazy woman would have assume she (OP) was agreeing with her and there would have been no escelation.  I'm not saying it's right, but there is a reason for the saying "sometimes discretion is the better part of valor."

[Sharnita]

Or OP could have slipped out the door and waited until Ranty's car was done and she might never had thought much about OP one way or the other.