It’s a well-known fact by now that superheroes and marriage aren’t normally compatible. As readers saw with both X-Men Gold #30 and Batman #50 in recent weeks, many heroes can’t even make it to the altar without things falling apart. It’s not hard to understand the logic of publishers like Marvel and DC. They need to keep these characters fresh and ready to face new challenges year after year, and having a stable romantic life makes that process that much more difficult. But in some cases, having a married character just makes sense. Maybe that isn’t true for Batman, but it certainly is for Superman.
Source: IGN.com Why Superman's Marriage Matters More Than Batman's