Board Thread:Questions and Answers/@comment-5037384-20151114025802/@comment-27180456-20160623000436

Zippertrain85 wrote:

I think Black Widow and Captain America should have a thing for each other (as implied in previous movies) but don't really have a formal relationship quiet yet from it.

The Russos specifically said that Black Widow and Captain America weren't supposed to be together, and nothing was supposed to be implied.