Why not contempt of court? What can I do???

My husband and I have custody of his 3 year old son. The mother is about worthless! She's supposed to have him every Wednesday and Thursday and every other Sunday. She has not taken a Sunday since the middle of October and she always cancels at the last minute. The biggest thing is she was supposed to have him for New Years Eve and canceled the day before saying "she couldn't figure out her work schedule...". We came to find out that she didn't have to work at all and she went out on a date. Our lawyer says we can't finnd her in contempt because nothing was detrimental...we didn't lose any money or were hurt in any way. What can we do about this deadbeat mother!!!