Tharayman: So this means I will have to buy 10€ of game(s) and then wait 3 months?
Ice_Mage: I take the support article to mean that you need to have purchased at least 9.19€ worth of games in total, and that you must have reached that threshold no sooner than 3 months ago.
Tharayman: There is no way around it?
Ice_Mage: Buy the game directly on the giftee's account.
This actually makes business sense if you consider it a moment: the extra personal data points (what games your friend is interested in, what she actually purchases, what she avoids, etc., all give Gog a better understanding of their customers) create a more reliable risk analysis for the transaction so that the possibility of scam theft is less than for a new random account that might be a trojan horse for copyright theft, which would only be disproved with a adequate sufficiency of recent legal purchases.
So, OP, assuming the GF is not a flash in the pan (no judgment) the best idea is to set her up with an account like yours but not yours: hers. :)