Sudden return of drive????

I have been married for over four years. Ever since my son was born, three years ago, I lost my drive and was something I did to keep my husband happy. Since then we had another baby a year ago. I have been nursing the past year and while I nurse I do not have a period, but my period returned August 1st anyways. About four days ago, I am pretty sure I was ovulating....my drive just reappeared.....THANK GOD!...I forgot how good that is! I am just wondering why I didn't get it back after I stopped nursing my son and how long this will last...is this common...I am sooooo glad that I am still physically attracted to my husband, just like on our honeymoon :)