How to learn a second language in your 30s and maintain your sanity?

My mom is in her late 30s and she decided to move to Europe. She has been there for a few months and has been trying to learn the language of the country that she is in, but it's just really hard for her to make progress in that language. She gets discouraged frequently and it just feels like she should just give up and move back to the US. What would you do in her situation?