Hi @Bianca2, Welcome to Forum Land. 
As @outlander noted, DBT stands for dialectical behaviour therapy. Some of us are working through the skills training component of DBT here in Forum Land: Let's do DBT We aren't progressing quite as quickly as we would like because life seems to keep getting in the way, but that's ok. You are extremely welcome to join us. The thread starts off with a fairly detailed description of DBT.
@MDT You mentioned on another thread that you are concerned about the stigma around BPD. You are right - it is a horribly stigmatized diagnosis. However, the stigma is just that - stigma. It doesn't mean that the horrible things you hear about people with BPD are true.
You also mentioned that you feel you will know one way or the other whether you have BPD after your appointment tomorrow. Remember, your psychologist is just one person with one opinion. You could go to a dozen different mental health professionals and get a dozen different opinions. Their opinion will be based on how many boxes they think you tick. The Diagnostic and Statistical Manual of Mental Disorders (DSM-V) is the book that mental health professionals refer to. It is just a book - readily accessible to anyone. Anyone can go and read the relevant section of the DSM-V and see whether they think a particular diagnosis fits. Remember all that critical thinking stuff you learnt at uni @MDT? You are the expert on your life. You are just as capable of reading the DSM-V as any mental health professional. You know yourself better than anyone else knows you. 