The club attempted to move on the three players during the January transfer window, but they all remain at Oakwell - with Cavare linked with several clubs including Portsmouth, while Daniel Stendel's Hearts attempted to bring in Thiam on more than one occasion.
But deadline-day passed without any move out of the club for the trio, whose Reds deals expire in the summer.
The end of the window also saw Barnsley fall to land any defensive reinforcements, with the club having not yet made any headway in the free agent market.
But despite a relatively small group of defenders to pick from, Cavare and Pinillos will continue not to be involved.
Struber, who confirmed that Sami Radlinger and Marcel Ritzmaier will miss the weekend derby with Sheffield Wednesday, with the latter suffering from a muscle issue, said: "They are not involved in my plans to play. This is for the next few months.
"We had a clear exchange together with the boys about the situation. For the boys, it is not a surprise, but clear.
"It is not so easy. I understand the players and it is not a simple situation for these players.
"They have no game-time and when they look in the future, it is not so easy to get game-time. They know they are in a difficult situation and not surprised that they will get no game-time in the next few months.
"They will stay here and work with us and it is not a situation to make me happy."