When I win in gambling, and it's a lot, I usually spend it on my girlfriend, and I'm spending all the time on her and spending all the money I earned from the gambling. She doesn't know where my money came from at least I can make her happy at least once a week and sometimes every day if I feel it. I always buy a new accessories for my everyday life usually headphones because they often destroyed quickly.
Lol well the good thing is that you're actually enjoying the merits of your winnings. that makes you and your girlfriend

Just make sure thatnyou don't push it too much as it may come down to a time when your girlfriend is the one spending on you if you don't have any money anymore
I don't understand why people spend their winnings because later you will regret spending them when you loose in gambling. Apart from that you can actually save those bitcoins and when you loose just deposit and recover.
On a personal note why spending money on girlfriend is a unidirectional thing ? Has your girl ever spent on you ? Think about it mate.