This is the Ring of the Pale Order description:
1 item: Restore 20% of the damage you deal as Health. This value is decreased by 4% per ally you are grouped with. You cannot be healed by anyone but yourself, your pets, or your Companions.
If you wear RotPO your companion will never heal you. I have Mirri healer, and Isobel hybrid tank/healer and they never use healing on you if you wear it.
Remove RotPO, and suddenly they start healing you.
There is only one exception - they use Crimson Font which is Undaunted synergy.
So either Ring description is wrong (companions can't heal you) or it's bugged (companions don't heal you).
Aldmeri Dominion (PC Europe via Steam)
The cowardly Wood Elves are best noted for their unwillingness to engage in a face-to-face attack; a Bosmer will strike at you from every side except the front. You won't cross swords with a Bosmer, but you might catch an arrow in the throat. Be wary in forests and jungles, and watch your back.