Ex wife made false statement to get an avo against me.

So my ex wife(35f), me (46m), has gone to the police and got an avo taken out on me and the worst thing is shes put my 3 kids on it. I havnt seen them since November. I would really like to know how anyone can walk into a police station and say back in 2015 she was pushed against a wall and punched in the stomach. And that qualifies for an avo to be granted. Now let's forget the fact we were married for another 5 years and had 2 more kids since 2015, on the affidavit it says you must include time, date and place it happened. How am I ment to defend myself against, 1,a complete lie. 2, all ive got to go off is 2015? How am I going to prove where I was when this happened, when I don't even have a date or address where this took place? Let alone it being 10 odd years ago now. Its costing me a fortune to fight this in court and she dosnt even have to show up as the police are prossicuting me. I'm guilty till proven innocent, automatically at an 80% disadvantage because I'm male. If you were the police officer taking this statement shouldn't they be asking more details? How can they take this to court and get a judge to agree to it when there's so little information. If I hurt her so badly why was there no hospital visit? Why wernt the police called out? Its her word is taken as the 100% truth. I don't know but if the person you were in love with and married too, did something like that to you, im pretty sure you would vividly remember where, when, day, night, probably what clothes I was wearing. It would be a rather traumatic experience i think. Its just utter crap. I miss my kids so much and I know damn well she'll be poisoning them against me. Its just not fair. The legal system has some massive flaws in this country.