If someone truly cares about another person, he / she would never suddenly stop contact.
The same situation happened to me. But I bought into the excuses (heavy workload, sick family member, crazy ex stalker BF harrassing her....etc.) and heartfelt apology when she returned (showed up on my doorstep, unannounced, last November) after months of not hearing one word. And it was the biggest mistake of my life not slamming the front door in her face.
Save yourself the effort of wondering why, Eve. I'd never stop contact with someone I care about, no matter what.