As has been pointed out the key phrase here (with Betazoids) is that of the Code of Sentience. Troi (Laxwanna) was often particularly blase about the minds of others, even stumbling through the darkest secrets...
My opinion was that if a Betazoid 'read' something they shouldn't the vast majority would consider it the height of rudeness to act on this information. That anything that was not disclosed voluntarily was treated almost the same way as a priest in confessional.
Of course the same source character implies that there may be many who view the code as somewhat... flexible and while they might not disclose the secret they would often push the character into doing so.
Perhaps what you have here is an opportunity for some character interaction and bonding?
DanG/Darth Gurden
The Voice of Reason and Sith Lord
“Putting the FUNK! back into Dysfunctional!”
Coming soon. The USS Ganymede NCC-80107
"Ad astrae per scientia" (To the stars through knowledge)