The Tower is a difficult card. It speaks of endings, break ups and sudden changes. Hit by lightening, the tower is set on fire and nothing much held in it can be saved.
The Tower, when used for predictions, announces drastic changes. For better or for worse, everything will change, even if just one aspect of your life is directly affected by it.
The Tower can be a card of relief. It can speak of leaving a house that was not the right place for you or even of the end of a mental or physical problem.
Like the Devil or the Hanged Man, the Tower is an easier card to deal with when drawn reversed.
See also this blog post about the positive sides of the Tarot’s scariest cards.