I think this is a beneficial attachment, not that we want to develop such a strong attachment to retreat that we can't function out of retreat, getting attached to the feeling in the retreat. Sometimes people get attached to the feeling when they come out of retreat, and start to confuse the feeling with the understanding that they gained and then think they've lost it once the feeling fades away. Remember, it's not just the calm and the feeling, the pleasant Vedana that we experience in retreat that we're after, but the transformation of our understanding that helps us to live more skillfully, causing less harm for ourselves and others. Because all feelings, all mind states are impermanent.
But the Wisdom, the Right View, the Right Intention that we develop on a deeper level in retreats, this is what we are after. It develops with the support of the silence and is then something that can help us live our life, our normal life much more skillfully. As well, because of the conditioning of the mind to get lost again and again in considering unimportant things so important, it's helpful to return to retreat so that we can again re-motivate our direction. And if you have the opportunity to do a lot of retreats, take it while you can, because you may not have another opportunity. But try to understand why you're doing it, not just to get high.