One of the things that has benefitted me is talking about it as it develops. I know that doesn't do you a whole lot of good at this point, but maybe try and mentally rewind and start with the small stuff, like "I feel like I want to tell you about the things going on in my life, even if they're not relevant to therapy," or something like that. And then work up to "I really feel scared about leaving and I feel like I need you."