back to the matter at hand:
if i understand your therapist he's saying, your life was bad- lucky for you though you found two friends (P&M) and they helped you through the hard times. however now you no longer need them and you should bid them farewell, cuz as long as you're paying me you're getting excellent excellent therapy and you don't need these friends so just thank them and bid adieu.
the problem with this reasoning is that he's validating them as friends, and as soon as you need them you can always fall back on them-
my humble opinion