Please explain to Theresa that you did not mean to appear to have her name wrong. The fact is that Teddy is sometimes used as a nickname (or diminutive form) of Theresa. When you called her Teddy, you were not being mean, just not using the form of her name that she prefers. Also tell her now that you know her preference that all of you will call her Theresa from now on.
It is good that she has adopted a name. I think you will find that she will open up and talk to you a great deal more now. It may soon be possible to convince her to allow you to remove her weapons and release her from the holding area. That would be a great development.
You have been an ambasador before and you will now be one again. Thresesa needs to be told about the Probe society you are building and how she can be an integral part of it. Show her the benefits of joining and you will soon have a new friend.
These are exciting times. Although you have been through much, the adventure is only just begun. Life is a thrilling thing to behold and all the more so to experience. Enjoy yourself, but don't forget to watch out for yourself and the others. Good luck.
Your friend, Space Turtel.