I realized we blew past your initial question of 'Where do I start?'. It is easy to get swept up in details of any situation and forget the initial quest which is a really important part of the process. What is your goal/s to finding help? And in what order?
Also, each therapist is different and it does you no good to give up trying to find one that helps. You might start with the therapist that didn't work out and ask if she has any suggestions with whom you may be a better fit. Most of the time, people just want to help.
In my opinion, the best way to combat negative thinking is using Cognitive Behavior Therapy. The original version which includes 'labeling' the thoughts is the most effective. Modern versions of CBT have pared down the process which tends to make the therapy less effective.