Is it permissible to wait for a married woman to marry her or to meet her in Paradise?

Thinking about a married woman is a waste of time, and there may be no good in marrying her. Ask Allah to help you forget her. Postponing marriage in hopes of marrying her might be chasing a mirage. Marriage is subject to Shar'i rulings, including obligation for those who fear falling into sin. A woman in Paradise will be for her husband from this world, the one she was married to when she died, or her last husband.