My girlfriend thinks my book is poorly written and decided to tell my mom - what do I do?

Hello. I'm a writer (not professionally published) and I wrote a book. It took 2 years to write and I'm mostly happy with it. My mom even read it and said it was good. <br><br>I just moved in with my girlfriend (24F) and she asked if she could read my book. I gave it to her not thinking anything of it, but she didn't like it. She said the dialogue was unrealistic, the characters were flat, spelling/grammar errors, and pacing issues. <br><br>Since she's an English major, I gave her the benefit of the doubt. I asked if I could get some specific feedback and said I'd be happy to hear her thoughts. She did a line edit of the first 100 pages, and I have to say, I agree with some of the points she made, but overall, I think she went overboard with too much criticism. <br><br>I was going to politely talk to her about it, but the situation got worse. She showed my mom the book and told her what she really thought about it. My mom called me super upset and said my girlfriend was right, and that I should just give up on writing because I'm "not cut out for it."<br><br>I'm angry at both of them. I confronted my girlfriend about telling my mom behind my back and she basically said, "Oh well, you wanted my honest opinion, and I told her because she's your mom and she should know." <br><br>I don't know what to do. I feel like my girlfriend overstepped her boundaries and went too far in trying to "help" me. <br><br>&#x200B;<br><br>What would you do in my shoes?