That's rough! Give me multiple GSW patient, cursing me out and threatening me because I won't give him a mouth swab any day, but when you get the snide little comments from patient family members that take digs at your integrity and ability as a nurse? Ugh! I've come home in tears after a patient's daughter told her mother (while I was in the room), "Don't worry, Mom. Some people just don't have compassion." It really eats away at you, and those are a couple of nasty scenarios that you had to deal with for sure!
Like yourself, I'm definitely not into confrontation, but I will agree with Cowboyardee: you're still a baby nurse and young in the critical care world. Add your youthful appearance, and you're a potentially easy target! While I don't think that's appropriate at all, I've seen it happen a lot, especially to the younger nurses with sweet, bubbly personalities. I imagine as you gain more experience, you'll learn to carry yourself with greater confidence and read the room better. Not saying you don't now, but I've certainly acquired a knack for faking it 'til I make it while in front of family members and patients.
It sounds like you're on the right track! This kind of stuff happens to the best of us! At the end of the day, I try to remind myself that we are getting a glimpse at one of the worse points of our patients' and their loved ones' lives. They're stressed, fearful, and want the best for their loved one. Unfortunately, that means they sometimes take that anger and frustration out on us! Keep your head up and keep on keeping on!