Don't get me wrong, I'm not saying that a person has to do something like write a book to feel good about herself after she gets dumped, but what I am saying is that I bet a lot of us are doing terrific things in the wake of the disaster and we're not even NOTICING what we're doing, whether it's great stuff for our kids or parents or friends or pets or people in our fields or altruistic stuff or whatever...and we have to sit up and take notice of ourselves.
what you are doing is being the authentic 'Antonia' in writing the books. It is what you do well. We all have gifts. I have recently received validation for stuff I have been working on, which has helped me to realise that the last few years haven't been marking time.
Interesting that your xh left when your book was published. My analyst friend feels very strongly that much MLC behaviour stems from a sense of inadequacy and not being able to measure up. [This can be in career, intellectual or even sexual terms] Your xh has hooked up with someone in a non-competing world that he can 'admire' but offers no real competition. In career terms he is her superior I gather. My xh hooked up with a talented musician. No competition.
My xh felt I was more successful than him, in terms of career and friendships. These were areas in which he wanted to excel. He still sends me stuff he has written, like some cats bring trophies. He is very bright but an underachiever - actually sets himself up to fail at times.
Much as I miss him, I really think i am better off without the negative aspects of his personality, which got more and more marked. And your xh - how cruel and sad to leave at the high point of your professional achievement.
I haven't tried internet dating sites, but know few people who meet through them. There are some non virtual ones I believe are good, because there is actually a vetting process.
But, the most successful recent marriage of a good friend was a random meeting, and another friend is marrying someone she met through doing charity work . . . . Both very nice guys.