Definitely not. Rhodey's character in the comics was never depicted as a Skrull. His role and development were consistent without this element of transformation.
In some comic arcs, the Skrull can be seen as bad due to their actions and motives. However, there are also instances where they have more complex and nuanced roles.
The friendship between Tony and Rhodey in the fanfiction is a complex and multi - faceted one. It's based on mutual respect, as they both recognize each other's skills and intelligence. Rhodey respects Tony's genius in engineering and Tony respects Rhodey's military acumen. They also have a deep emotional connection, which is often tested by the challenges they face, but always manages to endure, making their friendship a central and heartwarming aspect of the fanfiction.
Maybe Captain America. Captain America values honor and loyalty, and Rhodey with his military background would share those values. They could bond over their sense of duty. Rhodey might look up to Captain America as a symbol of leadership, and Captain America would respect Rhodey's skills and experience. So Captain America could be his closest ally in the story.