ToME: the Tales of Maj'Eyal

I was in combat... depending on Second Life to save me... and was under a DOT... second life did not trigger. Does DOT damage not trigger the skill?

Too many different things could have happened (perhaps you were hit by a sustain disabler before Second Life could activate?).

Care to post the combat log?

As said, a lot of things could have happened.

Second Life does NOT guarantee you survive a turn that otherwise would have killed you. It simply heals you a good chunk when you would die.

If you take insane amounts of damage in one turn, Second Life is not capable of keeping you standing.
If you have substantial healing debuffs on you, Second Life WONT grant sufficient healing to be a reliable rescue.
If you've been hit by disperse or what have you and SL has been disabled, obviously it won't save you.
If you did something foolish like take a step with stun + slow/burning shock (stun and shock together result in 10% move speed), nothing is going to save you.

Second Life is fantastic for protecting against single huge damage spikes, but if you've lost control of the battle then it isn't going to be enough.

If Second Life is sustained it ALWAYS triggers if a single amount of damage will kill you (after taking into account damage reduction from shields and lots of other talents. That is, it's a last resort talent).

And it will always add to your life the heal from the talent level.

However, it might not save you from dying from the next damage that comes your way.

So, either it has been deactivated, or you died from subsequent damage.