Suppose you have been in a relationship with your partner for several years (no marriage, no children).
Even though you still have strong emotional feelings for your partner (to the extent that you would claim to love her/him), you are no longer sexually attracted for him/her. While your partner can do without the physical aspects of your relationship, you feel to miss out on something important in your life.
Is it selfish to end the relationship, even though the breakup would be very hard for your partner and you don't want to hurt him/her? In other words: Is it immoral to choose sexual desires over friendship and mutual love?