We just know about mood and emotion. now lets come to our topic why women have dynamic moods and emotions.? Why men not emotional to the family? Why women close bond with kids and family? All emotion started from the brain’s limbic system. it's a size of bean near to our brain. If brains limbic system inactive you tend to be happy or positive thoughts. If brain’s limbic system active more negative emotions like anger, guilt. If the high activity of the brain's limbic system dominates your positive emotion with negative emotions. Not everyone has the same brain’s limbic system, Low
depression person has more activeness in the brain’s limbic system.
other than this there are so many reasons for mood changes related to family background, religion, country, education etc.
If you look for positive thoughts do reading, go out to exploring nature, always be relax and clam by doing yoga or anything that you like.