R.B.
My grandpa sounds like your grandpa... at 86 he is still a flirt.
My grandma was always waiting on him to finish up talking to what ever girl of any age he was talking to. She would always shake her head with a smile on her face and say "oh Bob come on I'm the only one who still falls for that". When ever we would leave ( after he finished talking to them) he would always take grandma's hand and smile and say a little flirting never hurts anyone and hopefully it brightens their day.
One time my uncle was with us and as we were walking away he said to grandpa " Dad that is disrespectful to Mom to always flirt like that" ( His flirting was just talking to them or telling them this or that looks nice today ( their hair, shirt, smile, eyes whatever..) ) My grandma chirpped in and said " its not disrespectful, if they don't know me he always introduces me as his wife of XX years and if a little flirting can brighten someones day like he does mine every day then Im willing to share his silly words". Then grandpa said " besides grandma is the only one who falls for those silly words." They grabbed each others hand and smiled at each other and we kept walking.
What I took away from that is love and trust really does go farther than jealousy. Grandma passed away a couple of years after that happened. They had been married for 58 years.