Yes tell T how you feel and the empaphy and understanding hopefully you get from the conversation does change things...not sure what kind of sarcasm you are getting...whether its deep hurtful stuff, which in that case I'd run from that T, or whether its a form of "play" that comes into the relationship? I know this happened with me, T was trying to be playful, but the subject was painful to me, ie I am afraid of lying on her couch and sometimes I;ll see the pillow placed from someone before me and T would gently tap the couch and tell me that some even lie upside down on it...we talked about this and she felt she shouldn't have "teased" me, but I told her that was fine, it was my own frustrations around not being able to lie on the couch, but the empaphy and look I got from T when she felt perhaps she'd caused the discomfort was nice, because growing up, any sarcasm would have become something-I_done or deserved, so it really is all grist for the mill...unless its abusive...