Kids an Unwanted Football?

How do we deal with a spouse that wants to make the kids a football, that is, something we struggle for possession over?

Say, I make a decision the ex- doesn't like (in this instance, asking her to do some stuff in the decree.) Then a lot of passive aggressive stuff starts to happen around our son. The yelling I can deal with (stay calm and rational and the ocean waves just spray around you!) but I can see the hurt on his face when his mom brings him by late, or not at all, or just shows up at the house to get something with a lot of barely veiled hostility.

Any ideas? Identifying the behavior is just viewed as criticism. Is there anything one can do other than insisting on the (minimal) rights of the decree?

Boodad

p.s. Two weekends a month and a night a week are a sad reflection on our society's valuation of the role of fathers. I wish hourly I had been able to get more in the mediation. You moms may have different views (fairly enough), but all situations are different, and some good men would like to be good dads more of the time.

My time with him, once every other week, is down to bare minimums... sigh.