I'm pissed

Okay, now I'm pissed. I just found out that a friend of mine (wait, make that a former friend of mine) has been lying to me. She is the only person that knows the whole story about me and my 'friend' "T". She has supported me through the rocky relationship that we have been sharing for the last 3 years and has stood behind me in every problem. I just found out she's been telling him things that she has told me the complete opposite of in regards to he and I. I'm so hurt and pissed. I thought she was my friend. I guess I'm learning everything the hard way lately. Maybe it is time to find a new job and move. I'll know better than to tell her anything again or to even believe anything she says.