Sorry to hear about those who've lost theirs. My condolences.
The short answer is a resounding yes.
The long answer is that I don't know if it would be possible for me to love or care about someone more than I care about her. There's always been a very close bond between us, and she's always been there for me despite my issues. At every school event, every soccer game, and every major event in my life without a second thought. She lives for her family, and is the glue that holds us together. I really respect her for it.
My Mom gave up any sort of a potential career to raise a handicapped daughter from the moment she was born. It wasn't even a choice - family came first and work wasn't even close. Even when she was working and going to school when I was really young, she still did everything with me and took me to everything she could.
Since day one she's been the most important person out there to myself and my family, and has done so much that it would be impossible to even comprehend or list it. She gave up her out-of-the-house life to raise us, and to make sure that her handicapped child has the best life possible, including fighting for disabled rights and doing absolutely anything she could to aid things along.
For the last several years, she's been dealing with health issues. What started with cancer in one area resulted in the removal of a lung, then it metastasized a couple of years later in spots on her brain, which have thankfully(!!!) been treatable through radiation and surgery. Currently, she's cancer free, though it's come at a cost unfortunately. Infection from one surgery years ago returned and hospitalized her for about two months last year, and she's been deconditioned since. Needs help to get up, use the washroom and go to bed. Doesn't walk all that well, so we have a walker and a wheelchair if need be, and help her at all times. A couple of seizures (sensitive brain from all that happened to it, with seizures resulting from lowered medication) have set her back unfortunately, but she's a big time fighter who still cares more about her family than herself.
It's very tough to see and experience, because I'm talking about my best friend and the closest relationship I will ever have. To say that I can't put into words how much she means to me is truth and not an exaggeration, because it can't be quantified. No words mean as much, even in tandem.
To thank her and show her I care, I go to almost every appointment, write her nice notes in cards, buy her flowers and help her every single day. Whether it's helping her to bed, giving her a drink, getting her food or helping her to the washroom or kitchen, it's the LEAST I can do. It's hard, though, because it's killing me inside (depression, anxiety) and I'm constantly worrying I'll lose her and I'm too young. So is she, which is more pivotal. But I want to make sure that she knows how much she means to me regardless.
I honestly think I'll crumble and be inconsolable if I lose her.