Let's give the male friend the benefit of the doubt for a minute. Let's say he dropped her off and he really is one of those inconsiderate, self-centered types that is in such a hurry that he can't wait to make sure his female friend makes it thru her front door.
With that premise in mind, Alma makes it to the front door but she can't find her keys. Maybe she misplaced them, maybe she lost them. Then what would she do ? Common sense dictates she would either call someone with a spare key, call someone and ask for a place to crash for the night, or go sleep it off in the back of her truck.
Did any of these scenarios happen ? Not that we know of. The male friend was the last person to see her, talk to her, and give her a ride.
I've come home staggering drunk many times in the past, but never so drunk I couldn't open my own front door to get in as long as I had a key. She has neighbors, friends, and family available should something like that have happened. So unless some creepy dude was camped out in front of her house at 3 a.m. with the slight chance (and I mean REALLY slight) that she would lose her keys and be unable to unlock her own front door, then this male friend of hers is still suspect #1.
I don't know about you guys, but at 3 a.m. where I live, there isn't hardly anything moving except for the critters that mosey around in the woods and the neighborhood cats that try to catch 'em. The idea that some scary guy staked out her house in the miniscule chance that she might not be able to unlock the door and walk in is almost laughable. The male friend's statement that he didn't actually SEE her go into the house sounds like nothing more than a weak alibi..........and I mean WEAK. It is possible that she might have an ex-boyfriend turned jealous stalker, but I haven't seen anything that supports that yet.
If this world has deteriorated to the point that individuals can't walk from curbside up to their front door without vanishing, then we all need to become martial art experts and start packing heat 24/7.
This sounds a lot like Christina Morris, Part II.