Why does my best friend’s mood always swing between extremes?

Name: Aisha Rahman

DOB: October 14, 2000

Time: 8:10 PM

Place: Delhi, India

Nasmate. I notice that my best friend's mood keeps shifting from being excited to sudden saddness. Its like even small matters could excite her, and even down her instantly at the moment. Her birthday is coming so, I was planning on gifting her a aura cleansing crystals, maybe that will help her keep her emotions stable. What crystal should I get her?