Even if they are not your lover, la difference will remind you of Eros. The different concerns, the way that the other gender looks at things. You will feel your own sexuality, the tension in the way we use language differently, the different ways we handle our bodies, and our mutual desire for contact and love. Being with someone who could or could not be a potential love interest, keeps you in touch with your own sexuality and your own femininity/ masculinity. Dress for that dinner. Go somewhere that you enjoy, almost as if it could be a date. Let the beauty around you infuse you. Be interested in the other and let the other be interested in you. It will keep all the juices alive.