It's never unfair to *ask* for what you need in a relationship. Fair is subjective. What one person may consider fair, another may not.
I'd ask him for what you need, but specify an end date. If he agrees, great! If not, then its up to you to determine if the relationship is worth the extra tension/turmoil.
In the mean time, use this as an opportunity to examine the source of your inner turmoil. If your concerns aren't reflective of actuality of the situation, then examine what thought processes are generating your emotions. This is a golden opportunity for growth.