Why are you with someone you don’t find attractive? Are you obligated to be in the relationship? Are you afraid of what happens without your partner?
A partner is someone you are happy to be with and if attractiveness is the sole determining factor, ask yourself what is unattractive about yourself. Why are they with you? Why don’t they leave to find someone else?
In truth, attractiveness is great for starting a relationship but the relationship will evolve to become more about the connection you both share. In-jokes are the best part, old arguments are the worst. But it’s something no one else would understand because it’s between you two.
Wake up with your partner, see them after a night of restless sleep or being sick for a few days. No one is attractive then and hopefully this shows that attractiveness is not the only requirement for loving someone. The only requirement is that you love them, whole and true, for as long as you can.
If you don’t love your partner, or find yourself doubting, have the courage to solve that difficulty. Be honest with yourself AND your partner. They are living with the hope that each day will be another in the story of your lives. Lying to them by hiding how you feel is building interest on a pain that could have been avoided.