Well as for treatment the use of Cognitive Behavioral Therapy (CBT) is probably the best for this issue since it helps an individual to focus on the present and not the past, since we cannot change the past. CBT has a premise that your symptoms are caused by negative thoughts, so if we change your thought process to be more positive and objective, then your symptoms will lessen as well. Here are some examples of CBT techniques that you can use to give you an idea:
So this link may help you, it contains a technique I use with patients called a thought record. It will help you keep track of any negative thoughts you have. You put the negative thought on paper, the emotion accompanying, the evidence to support it, and the evidence against it. Then I want you to come up with an alternative thought for the situation (more objective and plausible). This will help you change your way of thinking to be able to think more positive and not automatically go to a negative type of thinking.
In addition, these two worksheets are very good at helping to lessen negative type thinking. It can help you focus on the big picture and the objective/positive thoughts and outcomes.
Now I would recommend that you see a Psychologist/Therapist for a few months where you can get specific individualized CBT treatment, but I understand how costs can be of concern so here are some free CBT websites that could be useful for you:
Now remember CBT, and all therapy modalities, will not lessen your symptoms right away as it will take time because therapy is gradual, so you will have to be patient.