There's no fixed timeline, a couple of sessions can help for a couple of months or it could take months to even scratch the surface. A lot depends on your own willingness to participate but who you see and what their methods are can also effect your treatment.
For me, the local docs won't even do anything beyond emergency triage as they don't want to make things worse; I'm relatively stable but incredibly intelligent so the general consensus is not to unravel something they cannot put back together.
I have a lot of things I need to change about myself so I have no idea how long it would take. ---