I do think for us girls,its just normal.
Keep asking your girlfriend or wife what's bothering her only once. If she doesn't seem too keen on talking about her mood swings, leave her alone, and give her some space. Allow her to take her own time to bounce back in a good mood.
Managing and controlling female mood swings requires the four Ps—Presence of mind, Patience, Perseverance and Pampering. .Ugaliin mong makinig sa kanya,she may have swirling moods dahil upset or angry sya about something ,or it could something silly which made triggered her mood swings.Try to listen patiently,and don't try to avoid a seemingly boring convo with her.Madalas kasi its cause of pms related syndrome naming mga girls.Don't ever do things that will just annoy her.Wag mong hayaang maging out of control na yung moods niya.Be nonjudmental and don't be bent on being right even if siya ang mali.As much as possible avoid blaming,heated arguments and unapologetic rants.Keep a cool and calm behavior towards her ,it will then give a calming effect to her.You can also of course manage her mood swings with your sense of humor and satiate her food cravings which will surely lift up her mood.Lastly show compliments to ease and make her feel good.