My mom. If I have any good traits it's because of her.
She was born and raised, dirt poor, on a farm in Korea when it was still largely a rural country. Never even went to highschool (her fam could only afford to send one kid - so of course they sent the only boy ... and even if they could send any of the girls, she was a stepchild - her birth parents both died when she was very young - so she was dead last in line).
Married my dad who was an American soldier stationed in Korea, came to the states. They split up when I was four, leaving her with me and my older brother. Her English was still developing at that point, so to get a job she would go to places and get an application to take home to have my 11 year old brother fill them out for her. I can't imagine being in a country where I don't really understand the language and raising two kids on my own. That's a mind-boggling level of resilience and determination.
She worked two jobs (bagging groceries during the day, hospital janitor at night), so we rarely got to see her. She refused government assistance because that's just who she was ... so for many long periods of my life I only got to see my mom on the weekends, and my brother basically had to be my dad.
And even though she/we were dirt poor she always stressed the importance of doing as much as we can to help others. Although I don't share her religious beliefs (she's a devout Christian), we share many fundamental values (although if we're being honest here, I've had more than my fair share of slip-ups in being true to my own values).
I wish I could say I inherited her work ethic from observing how much she sacrificed for her family - not being able to see her kids very much, in order to provide for us. But she never complained and I had pretty much everything I wanted, so it was an embarrassingly long time before I realized what our situation really was. My older brother was more perceptive at a younger age - obviously due at least in part to him having to give up a lot of his own childhood to raise me - so he learned how to work much harder at a much younger age. Incidentally enough, he - the son of a hospital janitor - is now a doctor. I've been struggling a lot more than he did with finding my own path, but I wound up (about 10 years later than "traditional" college age) double-majoring in psychology and sociology, and am halfway through a master's program for social work (although currently on self-imposed sabbatical), and I'm currently working in the mental health field (crisis counseling). We both could have gone into a number of fields but seeing her focus on helping others - she does a lot of volunteer work for the homeless, through her church (and in general often goes out of her way to do what she can for pretty much anyone) - led us into professional careers of service to others, as well as advocating - however we can - for those in need.