I wouldn't feel bad AT ALL! This is YOUR wedding! You need to do exactly what it is that you want, regardless of what she is saying or implying. If you are really not comfortable, then switch TAs. There are so many out there, both good and bad. Sure, she's put some time in, but it's not like you have a contract or anything yet (I am assuming that!). It's up to her to find you those initial quotes. If they don't work out for you, no harm done.
We had some issues with my agent that were luckily resolved. She could've not cared one bit and left us in the dark on our own. When it comes right down to it, you need an agent who really cares and is going to do the work for you and yours guests.
You're the bride - remember, it's all about you! Good luck!