Woodpecker1:
Just a quick message to the people who have advised you to go self employed to avoid paying,who do they think pays for your child?
In an environment where the government is using the excuse of ‘further education’ and calling 16 + year olds,let alone 20, ‘children’ to get out of its responsibilities in terms of unemployment benefit liabilities and which allows home wreckers and their new ‘partners’ to profit from the same scam,I wouldn’t blame any innocent party in that situation to do whatever it takes to reduce their exposure to such legalised theft. 
As it stands the government has effectively removed unemployment benefit/income support rights from young people.While adding the insult of financial ruin on innocent parties and profit for the guilty ones,to the injury of a broken home and family,if a woman decides to run off with someone else taking her family with her.At which point if it was me while agreeing with the principle of the mother gets custody by the same standard I’d regard that family as lost and no longer of any interest to me in all regards including financially.Harsh but fair.In which case it should be those blokes who regard married/spoken for women,especially those with a family,as fair game,who need to be taking a long look at themselves.Then if they still decide to go ahead with such home wrecking activeties then don’t expect the innocent party to have to pay for the results. 