Just married... and I've found husband joined a dating site

I've been with my partner 12 years and we have two children aged five and eight. We finally decided to tie the knot at the end of last summer, but after five months of marriage, it's all over and I've thrown him out. I found out he'd joined a dating site, obviously with the intention of either having an affair, sleeping around or finding someone new.

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When I confronted him, he was so defensive and started calling me all kinds of horrible names. I couldn't believe how angry he was, like it was somehow my fault. It was a very odd reaction.

So, the marriage is over and I have to pick up the pieces.

I feel so humiliated and embarrassed about all of this. We had a big wedding in Ibiza with our kids and loads of family and friends, and now I feel like a fraud.