Just calculating.....his 1st wife was ca 13 a 14 years younger, the 2nd was ca. 16 a 17 years younger and bride to be is ca. 23 a 24 years younger.....
He seems to have a good relationship with his 1st wife, even after divorce
I guess enough time has elapsed since 2002 for them to think it over. Plus wife to be is clearly not the reason for their divorce.
So 1 and 3 can actually built a good relationship with eachother.
I know someone who is/ was friends with the first wife. According to her Lilly Sayn Wittgenstein seemed to be very friendly and easy going, lots of friends, very fun loving, good network of interesting people. She is a typical "upper class kid". If I recall it right: Aristocratic background, very posh private schooling, very sheltered, no academic interest and she was 20 when she got married (and he was 14 year older). More to please her parents and because she thought that was what society expected of her. Bit of a Diana/ Charles story without the sad parts.
She then got a bit bored in the castle, the representation, the "boring jobs", the countryside. She had given birth to the heir when she was very young and was craving for "life". Bascially she had done everything what was expected of her by the age of 21 and then got bored in "everyday life" and did not want to carry on for the next six decades like that. She basically grew up after she was married and realized that the life she led was not the life she wanted.
There was a second pregnancy announcement that just faded (no idea what happened there), she was partying hard (often with her husband with her, but she was clearly the "wild part" and I think they both realized that her gist for life and excitement and the rather conservative castle life was drifting apart from what was demanded of her so they seperated. First they tried and make it work - I remember a TV report that she stayed fit by using roller scates (THE thing) in the castle garden/ park, talking really friendly to everyone she met. There was never any talk of cheating, or improper behaviour, she did not want to hurt anyone, she just wanted way more fun/ excitement than her role gave her.
AFAIK there were never any hard feelings or openly discussed differences. It was just she moved to Munich because she was a modern city girl not suited for boring life in the castle. I think they were never madly in love, it was more a "very well suited" story as they were both from important aristocratic families and her family seemed to have thought that she "would grow into her role". My friend said that she was a bit "shallow" but always very friendly, never "posh" or arrogant and just one of these "spoilt" upper class kids who never really had to worry about bringing bread and butter on the table. So AFAIK the split was friendly, they just realized one day that her gist for life and what he was looking for in a wife was more and more clashing and he re-married a more conservative woman in the hope it would be easier to settle down.
As he has been married quite a few times now you can imagine he might not be the easiest person to be married to - or the reasons Lilly gave might not be everything that went wrong. But she was nobody for airing dirty laundry, they made sure they appeared as pleasant as possible to each other (in public) while breaking up.