Good to hear things are improving for you personally, although it does sound like it's you that's finding your feet rather than getting better groups. You should NEVER have to apologise as a healer for getting mobs off you, they shouldn't even be on you in the first place.
Basically you're right but I've been kicked times many enough
so I prefer apologize my groupmates than sit in queue once again
Its just one single time I've been kicked for using Cloud Mind, but better to be sure, right
Because mobs off from me means mobs to someone else. DPS aren't equipped to take hits and even tanks have their limits
too many mobs will kill anyone