We also have lots of butterflies in the garden at the moment, and have also observed them mating as you describe. We have lots of tiny blues, several different Clouded yellows, Southern whilte admirals, Painted Ladies, Small coppers, Brimstones, Orange tips, Red Admirals, Tortoisehells, Peacocks, various fritillaries and also lots of different moths. The most exciting being Convolvulus Moth, Great Peacock moth, Elephant Hawkmoth and Privet Hawkmoth. All these because of a good variety of plant life for them to breed and feed on.
As you say Umbrian, gardening is never boring, its so much more than digging planting and watering.