The duped 64-year-old – named only as Jan – said he had ‘no clue’ his bride had been born a boy.
The shocking revelation only emerged after almost two decades of marriage when a cousin from his wife‘s native Indonesia finally exposed the truth.
Jan told how he met ‘Monica’ in 1993 when she arrived in his home town of Antwerp as an au-pair to his sister’s children.
He described as her ‘very beautiful and feminine’ – but said he now understood why she was ‘no good at ironing’.
Jan told Belgium’s Nieuwsblad daily paper: ‘My second marriage was on the rocks at the time and we quickly fell in love.
‘I thought she was an attractive woman, and she was all woman – she had no male traits.
‘She was 27 years old at the time, so I asked her if she wanted children.
‘I was glad when she said she didn’t as I was 44 and already had two of my own.
‘Over the years she said she was taking the pill, and even during sex I never noticed anything, though now I understand why she always used a lubricant, which is apparently normal among transexuals.
‘She was always a good mother to my children, and also a fantastic cook, though we wasn’t that great at cleaning and ironing – and now I know why!’
But Jan said the relationship had begun to suffer over the past two years as she insisted on staying out late on her own wearing ‘very revealing outfits’.
He added: ‘She would wear tiny tops that revealed a lot of flesh and had more than 100 pairs of shoes.
‘I also caught her ogling pictures of young men on the Internet.
‘But I didn’t suspect a thing until a cousin of hers came to visit and let something slip.
‘I mentioned it to my son and he said he’d heard a rumour too that Monica used to be a man.
‘One evening I confronted her and she finally confessed she had been born a boy and had a sex change operation.
‘My world collapsed in a few seconds. I was horrified. I feel like have been violated for almost 20 years.’
The couple are still living under the same roof after a judge refused to grant Jan an order to evict her.
But he added: ‘We live in separate rooms and rarely speak. What Monica has done to me and my family is unforgivable. I just want her out of my life.’