It's hard, without knowing exactly how the future is going to pan out, to decide who are the winners, and who are the losers, in this whole debacle.
Assuming De Gea refuses to sign a new contract at United, and leaves on a free next summer, then United are certainly losers however. If De Gea also refuses to play for United this season, or Van Gaal sticks to his stubborn guns and won't pick him, then United are even bigger losers.
If De Gea still wants to sign for Real, and hasn't been put off by whatever it is that has happened here, then Madrid are the biggest winners, as they'll get a player they were willing to spend nearly £30m for free in 12 months time. They've got good enough keepers to last them this season in Navas and Casilla.
De Gea is a loser in this who debacle too, best case scenario he ends up playing this coming season at a club he doesn't want to be at, for a manager he dislikes. Worse case scenario, he sits in the stand watching for the entire season, and loses his place in Spain's European Championship squad.