1. Person can lose their self respect and dignity to survive in the in-laws house.
2. The ex- and the current wives can be under the same roof.
3. Brother and sister (treated so once) can get married (just can't digest).
4. Just work under a person who ruined the family and continues to do so.
5. Explain all the personal issues in public (just can't imagine).
6. Forget the past and participate in ex-partner's wedding with entire family.
Just thought of only few, but certainly more are there which can be added as you people wish.
4