My ex disappeared with my kids after meeting her new man

DEAR DEIDRE: Since my ex-girlfriend met her new partner, she has moved out of town and won’t let me see my kids. 

I am 39 and she is 36. The children, both girls, are nine and seven.

We split up quite acrimoniously two years ago. The girls live with my ex but used to stay with me on alternate weekends and during the school holidays.

A couple of weeks ago, I went to pick them up as normal but nobody answered the front door and my ex didn’t respond to any of my calls or texts.