If she is incapable of living without the suit, and thus is always in the suit I would definitely label her as a cyborg. You might make it be a point of discussion in your story though, to reinforce the point that she can't live without the suit, to explain the definition as cyborg.
This is just random brainstorming, but you might try to expand on the suit a bit more than just "the armor she's wearing so she doesn't die". Perhaps have the suit have an inboard AI that talks to her, sort of like Jarvis for Tony Stark in the Iron Man suit. That way she can have some dialogue options even if she's forced to be alone in some social situations.
Or perhaps have it be that she tinkers with the suit, and has hacked the onboard AI to give it more personality, so she can have a buddy. Or perhaps also she and the AI tinker with the suit to allow her to have more access to various abilities. I mean, if I was stuck in that suit 24/7, I would spend a great deal of my time finding ways to expand my abilities and functionality, if only to stave off boredom. And I don't mean things that are just military/combat in nature. But things like "hey! I've got wifi in here now! I'm totally streaming the Starcraft 2 World Championships!" or "I've found a way to graft wheels onto the suit, so I'm going to go try out some inline roller blading...but on a mecha-scale." Or, "I've learned how to piggy back the sensor package this suit comes with into the civilian bandwidths, and I've been able to coordinate the police search for our target based on the information we have. They've cornered the perp at this address, and are establishing a perimeter. Let's hurry." Things like that. Incorporate the suit into her life, and then ask yourself "how would she deal with this on a day to day basis?" Perhaps do some research on people with prosthetics, and how they learn to incorporate and manage the new equipment into their daily routine, and then adjust that to your story. For humor, provide a downside to some of the tweaks she's done. Like the above mentioned "civilian bandwidth hack" now makes it where she's getting irregular spam chatter about various things like minor traffic violations. "Damnit! 3000 illegal parkings in this city every hour!? Savages! Learn how to park your car properly!!" Etc.
Or, totally ignore everything I've said. It's your story, do whatever you want with it, seriously. I just saw the image, and your short synopsis of her situation, and my brain instantly started brainstorming. I tend to do that a lot, and then posting it.