Low sex drive

Weird questions....but my sex drive is always on the low side. I know its mainly because i am always tired from looking after my 3 children. When i hit bed i just want to sleep! My partner is always up for it but i just say no and we go more then a week without it sometimes. I really want to increase my sex drive. Im now taking a-z vitamins just to help me with low energy and anything else missing. But is there any herbal meds people have taken to increase their sex drive that has worked?