I'd say its natural to speculate on what's happened because its so unusual, but its definitely uncalled for to point fingers at people. Seen plenty of people accusing her partner online but he might have a watertight work alibi (the police would know this) and its hurtful to do that. I'd also say that if people are going to speculate it should at least be something realistic, there's too much being said thats crazily far fetched.
You've just got to trust the police, there's an asymmetry of information here as we just get fed bits through the media whereas they have much more to hand, and they will choose to release whatever information is beneficial to release for the purposes of the inquiry.
The falling in the river theory doesn't seem to stack up very well, but the police explicitly said that from day 1. You'd think a body wouldn't be too difficult to find in that area of the river and thats certainly what the search specialist appears to have implied, yet so far nothing. Would also say it seems like a bit of a stretch that someone youngish, fit and healthy would randomly fall over into some shallow water and be unable to save themselves in the first place, and supposedly a strong swimmer. The dog would also have been going crazy next to the river if she'd submerged there you'd have thought.
You can almost 100% rule out a canoe man type scenario, you can see straight away she's just a normal loving mother, and normal people don't do that sort of thing, plus its ridiculously difficult to pull something like that off. John Darwin was a very different scenario, only his wife knew and have to remember this was back before social media or camera phones. It would be too difficult to avoid someone seeing you now. You can also rule out self harm, its totally implausible you'd kill yourself somehow somewhere where nobody would find you, plus there's no evidence she was in a bad frame of mind.
So I think you can narrow it down to either 1. falling in the river or 2. being abducted. Its a really odd case because if you were attacked by someone you don't know, usually you'd expect that to be opportunistic? Not in broad daylight in the middle of the morning where any random passer by could see. The lack of CCTV near the caravan site is a red flag but even still, anyone coming from there to take her is risking being seen by other people on the site (there's no way a whole community would keep quite about that if anything had been seen), they're risking a random walking past in the field, and they're also taking a big chance as she was on the phone at the time, she'd have been likely to gasp or say something which her work colleagues would have heard. If she was being targeted you'd at least want the cover of darkness before attempting anything like that. This is probably why the police are going with the river theory in the absence of evidence.
Nothing seems to stack up.