In the US... Assuming you're talking about two people married to each other, no, one can't still be married and the other be divorced. They're either both married to each other or both divorced from each other. It is possible that a divorce was granted without one party being aware of it, if they were unable to locate that person to serve notice of the divorce, in which case they do a divorce by publication (publish a legal notice in the newspaper).
Yes, if they cheat on each other with infected people.
Domestic Partners
they got married because they loved each other and there were the only two people left on earth at that time
You are two people who are married to each other who are separated.
Because they love each other and its an ancient traditional thing
People get married in Japan for the same reasons that they get married anywhere else. Two people form a partnership in order to have a family, for mutual support, often for the raising of children, and because they love each other.
Yes, people have the capacity to like other people based on shared interests, personality traits, and emotional connections. Establishing friendships and forming meaningful relationships are common ways in which people show their affection for others.
No. You're still married, just not to each other.
No, they are not married to each other.
I would think not. People get married because the love each other, not so they can attend every social event of the century.
Sure, business marriages can work. Couples get married for a bunch of different reasons, and even if two people don't love each other when they first get married, that doesn't mean they won't end up loving each other.