Marrying Jennifer is the worst thing that could have happened to him, because the marriage was doomed (which was both of their faults) and Anthony has a "if at first you don't succeed, give up immediately" outlook on life.
So as a result, he gave up on the idea of being a husband and father, and not only that, he gave up on being a grown-up.
He hides behind this smoke-screen that the reason he no longer believes in marriage is because a) the financial trauma he suffered, and b) a distrust/hatred of women.
But I don't buy either of those things. First of all, while I'm sure it sucked being taken to the cleaners by his ex and her shyster lawyer, when have we ever known Anthony to love money *that* much? He's constantly throwing it away at luxuries, gambling, and maintaining his retinue of ballwashers. He lost great amounts of money on Citadel stock and selling his mansion at a loss, and neither of these things seem to faze him to a great extent. He's the "easy come, easy go" keed.
And as for the badass misogyny "girls are icky" stance? Nah, I don't see it. Anthony still puts women (well, little girls) on a pedestal. His goblin of an ex-wife didn't do anything to dent his fascination with the fairer sex.
No, what really happened is that he tried venturing into adulthood, it didn't work out, so he immediately crawled back into the womb and has stayed their for the past ~25 years. And that's how he'll die. A manchild. Just because things didn't go his way and he can't handle challenges or setbacks.