Your cousin by marriage.
Your brother's wife's cousins are not related to you and the English language has no special term for that. The same applies to the cousins of a stepbrother's wife.
If you are close to your step-brother, or to his wife, you can call her your sister-in-law. If you are not close, you can call her your "step-brother's wife."
Ellen Cousins
That would probably be your cousin-in-law.
Why would anyone want to sleep with their cousins wife? Are you perverted or what?
If the children of your great uncle's wife are also your great uncle's children, then they are your parent's first cousins, and your first cousins, once removed.If your great uncle's wife has children from a previous marriage, they are not related to you because you have no common ancestor. However, if they were very young when their mother married your great uncle, it may be convenient to treat them like "members of the family" and call them your first cousins, once removed.
He doesn't have a wife!
Your cousin's wife is not related to you, so her cousins is not related to you unless she has some family connection to you besides being the wife of your cousin.
yes, they might be "distant" but their still cousins
Theodore and Franklin Roosevelt were distant (fifth) cousins. Franklin's wife, Eleanor Roosevelt , was Theodore's niece .
Barbara Cousins
In genealogy terms she would be "spouse of your first cousin."