I am glad you are sharing. It does help to talk about things. Your gauging on how much to "Restrain" around certain people is very much how people "Act" around certain people and friends. They have an image to uphold and they may act differently with so and so then they do Steve. They may act different with Mary then they do Sue.
I know what you are going through as I've had a close friend snap before, and it does hurt. Some people just don't really let all the good you've done for them sink in until after the fact. She may realize it later, maybe bring it up, maybe not. She may never realize it. People are all different.
I can tell you, I could handle that snarkyness. I personally love snarky and I will go right back and join them.

But I do it very nicely. I wouldn't say I am a snarky person, but if someone is, I love building up snarkyness with them in a fun manner. It almost becomes a friendly competition to who can be more snarky if that makes sense.
Sorry, LP. Just because they snapped also doesn't mean they don't want to be your friend... unless they said otherwise. Just give it some time. Contact me if you wanna talk further.