Lock target via cycle through

Heya! I apologize in advance for my english, hope you will understand me.
I like to use cycle through feature (shift/ctrl/alt + mouse wheel) but there is one big probem: cycle through feature allows you to use only one skill on selected target and, if you had another target previously, your target returns back to him.
For example, playing as healer, my current target is tank, then something happens and now one dd runs around in agony pain screaming "Haaaaalp!", I must to select him and heal a bit/remove debuffs e.t.c. I choose him using cycle, use heal and... my target is back to tank, but I still need to heal that poor buddy, so only solution is to cycle again and again to him wasting time or click on him what I do not like.
So how can I lock him after cycle? Beforehand, keybind "choose last target" works only for enemies, so it's not an option (by the way I'd like to know how to use that on everyone, if possible).
Thanks in advance.

Target cycling gives you a soft target, so that you can quickly cast situational or one-off actions on a different target then go back to what you were doing. If you'd like to convert your soft target to a hard target, you just need to press the Confirm button. If you have a spare mouse button, you could bind Confirm to a mouse button. By default it's bound to Num0/(empty).

/keybind
System
Confirm




Target Last Target actually does work on party members, but only considers your hard targets.