Okay, here's a little bit of sage advice for you.

FIRST. You need to realize that you fucked up badly with your police encounter - so that you make sure to never repeat the same mistakes again. Understand that the only reason police search for evidence or ask questions is because they DON'T have enough evidence to charge you, and are hoping you will give it to them. The vast majority of convictions are secured by confessions from people that are too dumb / timid to know and understand their rights

For example: Gave the police your passwords? You don't have to do that. Know your electronic rights. The police don't have the right to force you to disclose passwords for anything. It's THEIR job to collect evidence against you; don't do it for them.

The next time you have an encounter with the police and they start asking you investigative questions, say this:

"I'm sorry officer, but I don't answer law enforcement questions unless my lawyer tells me to, and I don't bother to call my lawyer unless I'm being charged with a crime."

That's the simplest way to shut down a police fishing expedition.

If you ARE arrested: Invoke your rights. To remain silent. To an attorney. Explicitly.

In the future, also consider password encrypting your private electronic files and your private communications via a service like Pidgin OTR.

SECOND. Don't fuck around with girls under the age of consent in your jurisdiction. Not. Worth. It. Yeah, you only gave her a massage, but what if she had been down for more? Can you say that you would have definitely turned her down? I doubt it, and I'll bet her memory would have been a lot better in that case too. Then you could have really been in some serious shit.

THIRD. Consider filing complaints against the judge who signed the warrant. To his supervising judicial body, and to the state bar association. If what you say is true, it sounds like the police didn't have probable cause to believe a crime was even committed, let alone that you were the one who did it. Signing a warrant without probable cause is unlawful. While you probably have zero chance of winning a lawsuit against the judge (due to qualified immunity), you could help to get him disciplined in some way. Unscrupulous public servants will remain unscrupulous until they are called out on their behavior. Make a difference for the next guy.

FOURTH. Time to end your relationship with your friend, let alone his sister. Make certain she pays a social price for bringing all this shit down on your head. Don't be Ben Affleck in Gone Girl. Don't let her get away with it.