Horse in skyrim??? Questions!!!?

Maddening it is...

The horses cannot be left behind or stabled (when you fast travel), unless you never rode it in the first place. Once you do it will follow you everywhere, except when you take ship in the add-on.

I find horses of little value unless overburdened with loot.

The horse will run away (about 200 yards) if a very strong foe/animal attacks. Otherwise it will attack, getting in the way much like other followers. If left in the wilds or outside a cave or ruin it might get killed by random incidents.

And, then there is Shadowmere who gets jealous and will Hide (turn invisible, and stays in the last place you rode him to) for 10 days if you dare to ride another horse.

http://www.uesp.net/wiki/Skyrim:Horses

http://www.uesp.net/wiki/Skyrim:Shadowmere

If you fast travel to a city, your horse will automatically go to the city's stable. You can leave your horse anywhere really, if you fast travel to a location or dungeon, your horse will spawn next to you.