Commitment comes naturally to you. You're not the type of person who thinks that true love is something mystical and magical that just happens to you in a moment of blind luck, and never needs any maintenance or upkeep thereafter. You recognize that partnership, even with a lover, is a serious business, one that takes work and effort and consideration.
You don't enter into a commitment lightly, and once you do enter one, you take it seriously. For this reason, you're made for a long-term relationship. In fact, you may go through a series of long-term love affairs before you find the one that stands the true test of time. Just as you don't enter a relationship lightly, you don't break up lightly; you'll put in the effort necessary to make things work out with your sweetie. But you're practical and levelheaded enough to know not to force it if things just aren't working out. Because you're so stable and levelheaded, you serve as the rock in your love affairs. You probably don't suffer from a 'savior fantasy,' but you do like the feeling of being there for your lover, helping them out in any way that they need and making sure that your bond is strong.