All relationships can be saved if both parties are committed to the relatioship and willing to take steps to reair them.
All relationships are based on having certain needs being met. Healthy relationships are ones where there is a mutual meeting of these needs. When your emotional needs are not getting met the fire of love, the passions, the intimacies even the friendship cools. There are 10 emotional needs that everyone needs to have met, at least to some degree.
It is just a matter of understanding those needs and making a real effort to meet those needs.