Dog help

Shelby • Mama to Sydney 💕 👧🏼 I love being a girl mama!
Hi everyone,
This post is totally unrelated to ttc, periods, that such thing. However, I'm out of options for advice, so I'm hoping maybe someone can help! Here's the situation:
My dogs has what I believe to be seperation anxiety. When I leave and out her in her crate, she barks. Also, when she goes into her crate at night, she barks throughout the night. I'm not sure what else to do to get her to not bark as it is very difficult to deal with considering I work during the day. She is 6 years old, and hasn't really had this problem much since I've had her (when she was only about 2). Does anyone have any advice? Or have you gone through this? If so, PLEASE share what helped! 
Thanks everyone!