“It’s happening now!” This is what I hear a fair bit when I see clients who are experiencing Post Traumatic Stress Disorder.
They feel that what they experienced in the past is happening to them again - right now - and they act according to that threat. In other cases the effect of PTSD impacts relationships and behaviour because they have not worked through the anxiety, depression or other feelings caused by the trauma. They hold-on to the situation in the present.
Treating PTSD is needs to be very customized towards each client. The main reason is that some may respond well (and be able to) discuss the past trauma, and go back and re-experience it. However, even if this can be done, it may not be curative, and it needs to be done with a lot of caution. In other cases of individuals suffering from PTSD, we work first on the ancillary conditions and behaviours thus beginning to improve and restore quality of life in the present. This may lead to a significant amount of "Here-and-Now" work with the client within the therapy session in order to help someone with PTSD live in the present.
This does not mean that the trauma will not replay itself, but when it does, or when other signs of the past come up, they can be handled differently in the present moment through improved perspective.