Everytime!
Every second is precious, we spend our time mostly together with our family during morning and evening. By doing this weekly or 2 times weekly, or just a random day from a week, we spend time together but not during mornings and evenings, but during midnights and overnights. It may sound stressful, or tiring but the energy could still be replenish after eating together with these peeps.
I would love to have a date with friends and family than to date my Girlfriend, dating with your Girlfriend alone would not make your relationship longer, but instead letting your Girlfriend know who your friends are, and knowing her friends are creates a strong relationship bonds. I think its not just about you and your partner's relationship. But to everyone around you.