Hey I have been diagnosed with Chronic Complex PTSD, and have been having therapy for it. As for the treatment it depends on the approach, it is normally either EMDR which involves accessing memories whilst watching finger movements it helps to process the memories. However I won't lie it does bring memories to the surface and can hit a few days after the session quite hard. The other way is DBT and prolonged exposure, basically they will teach you ways to cope then prolong your exposure to memories to help you become less affected by them when they arise in day to day situations.
It is quite hard, but ultimately worth it... I also find the PTSD forum online a lot of help....