I don't think your children are necessarily "unwanted." I just think 7 days of consecutive, single parenting is a bit much. I am a Mother and when my husband and I split, we did every 2 days and it worked out to where we had every other weekend for 3 nights. Now that may sound like a lot on the child(ren), but I think it's all in how you perceive/project it.
Plus, we have different roles and maybe your new single life is calling for you to have a little fun and you dont want to be tied down with kids.
IMO, there is nothing wrong with how you feel, but trust me, your children are not unwanted, there Father is just wanting some "me" time.