Fraudulent Beta Readers?

Beta Reader - a person who reads a written work, generally fiction, with what has been described as "a critical eye, with the aim of improving grammar, spelling, characterization, and general style of a story prior to its release to the general public."

                        ^^^Straight from Wiki^^^

My take : someone who reads a WIP with the intention of finding and correcting grammar, punctuation, spelling and any mistakes/faux pas that may be within. 

What I expected: An unbiased someone to critique my work, tell me if it flows nicely. If the characters stay true to their personalities. Tell me if I made any grammar, spelling or punctuation mistakes and GIVE ME FEEDBACK.

What I got: Ignored from ONE beta reader who has not replied to any of my messages.

I've recently had a problem with one beta reader for Caylee. Or, at least it has the potential to be quite a problem. About six or seven months ago when I'd had all but the final chapter finished for The Descendant, I sent off a bit of the book to four or five different beta readers of different ages, with different tastes in reading to see if my writing better suited my target audience or if I needed to tweak some things a bit more.

Almost all of my beta readers responded to me with feedback in a timely manner. Two haven't but one of them, I've spoken to and things are okay there. For the one person who didn't contact me with feedback and still hasn't contacted me, things are definitely not okay. I've sent her two messages in the last week or so and one back in November. I haven't gotten a single reply from any of them. It will be seven months exactly tomorrow since I've sent the chapters off to her. Seven months is BEYOND ample time to read five-six chapters.

I've heard many a horror stories about an author's unpublished, copyright free work being posted on fan-fic sites being passed off as another's words and I am just hoping that is not the case with me. I knew this beta reader. Or at least, I thought I did and if this is even a possibility of what could've happened, I definitely don't want it to happen to anyone else. 

I know, I know. I should've been more careful who I trusted with my babies and should've only sent it to people I really trust. But, I made a mistake. An error of judgement on my part. One, I assure you, I will not ever be making again. I will not mention her name, because I believe it to be unprofessional and moot, to be honest. She has my chapters and if she decides to do something with them, then she will. I will, however, urge people to be extremely cautious when allowing others to read copyright free pieces of your own creation. People are not what they seem.

So please, please for the love of books, be careful who you ask to beta read for you.

--A.