Sex drive

Ladies how do I get my sex drive back. It seems like it went away after I had my twins. They are 6 now and things are way easier than they used to be but I find my self just always tired. My partner helps a lot with them but I still am so tired during the day. My partner sometimes makes comments to me about wanting me and I just laugh about it and he has expressed to me that he would like for me to initiate sex more often but I honestly am just never in the mood. He initiates it all the time and we manage to have sex about min 3 times a week. I enjoy the sec and I get in the mood after he initiates it but i would like to initiate it or feel in the mood and make sure he feels loved. Help!