I are kind of an engineer, but there's a verb missing or something in your description, so I'm not entirely sure I grok your problem.
I'm gonna guess...you want to hang two hammocks side-by-side, off the same pair of trees, but separate them. So you're thinking some kind of spreader bars that would push the suspension lines of the two hammocks apart.
I'm thinking maybe somebody has done this already. I think you need only separate the two hammocks at the head, the two hammock occupants can play footsies with each other OK. The compression forces on that bar would be a function of the weights, the length of the suspension triangle from the bar to the tree. Thumbnail sketch, twice the compression force you have on spreader bars for a bridge hammock, since there is twice the weight.