So I was doing a companion quest earlier. For some reason, they decide to send me to a Dwemer ruin at lvl 12. It went okay, Falmer falling to my greatsword with a swing or two, until that is, we came to the end... Of course, I had Lydia with me... well, in the last room is some kind of named Falmer caster and one of those Dwemer Centurion steam robot things. Yeah, kinda made me mad.. I mean, I'm lvl 12 and this was deemed appropriate scaling? Oh well.

After much reloading, and much resorting to letting Lydia tank while I threw out all the magic of scrolls I'd been saving, we finally downed both the caster and the centurion. (oh, I forgot to mention, I was out of health potions because in the room before I had to fight 3 of these spitting worm things that just wrecked me.. again, not sure why they sent me here at lvl 12)

Anyway, we barely made it, the bad things are dead. I look and make sure Lydia survived, she did miraculously, despite my indiscriminate sword and spell slinging. So, I saved the game and went about my merry way. Anyway, I get back to Whiterun, she's nowhere to be found... "oh well, she'll catch up" I tell myself. Yet, after a fast travel, resting in my bed and doing other quests... still no Lydia. I started to get a little worried.

Well I just finished a quest with Farkas, and returning to Breezehome from Jorrvaskr, I open the door and there is Lydia! Not only that, as I went upstairs, she greeted me, telling me how glad she was we were friends, and gave me a gift! Honestly, kinda made me feel all warm and fuzzy.

I <3 Lydia

Lydia:I am sworn to carry your burdens...

me: Not his again!*Sword to face*

That's how much i love her ._.

Sounds like you may have told her to part ways and she went home. Easy to do by accident if you are on the PC as the menu bites.

She gave me a gift once also after I had sent her home and went back to visit.

If it wasn't for the issue of having to use the console to level her properly every ten levels, or to use the console to make her marriagable, etc., I would use her all the time. I am hoping that promised patch for January that is supposed to fix quest and item glitches does what it's supposed to.

I =|==> Lydia.

As in, stabbed her with a dagger as a sacrifice for one of the Daedric Shrine quests.

That's kind of something I've been wondering about, and I've seen a lot of conflicting information on this. First of all I play on Xbox, so the console is not an option for me.. but, I always used Lydia on my previous character, and though I never got real high level - I would take on giants with her all the time, she would take a smack from a giant like a pro. So she must scale to some degree yeah?

Oh well, regardless, I keep her in the best armor I can make and I'll take her everywhere with me anyway. (in fact, her armor is better than mine lol, I love the look of the Ancient Nord armor that I'm just sticking with that and leather boots)

I took Lydia with me into the Labyrinthian at level 12. She didn't make it back out...