What are the symptoms of perimenopause? What should I, as a husband expect or look for?

My wife has headaches, mood swings, loss of libido and cannot sleep very well. Will a treatment help her if it is determined that she is in this state of menopause? She is 38 years old and I have notice a considerable change in the last year. I thought it might be our relationship having issues but, nothing I do or talk about seems to ease any of her stresses. Her cycles are irregular and her flow is also heavy at times. She has complained, saying her body feels like it is on fire. Is this a hot flash? She has gained weight and seems to cause her some pain and bleeding. HELP please!