Spoilers for the most recent episode of The Walking Dead are below.
As we all know, The Walking Dead is a show where happiness is only shown in fleeting sceces, and even though years were spent watching the evolution of the eventual courtship between Rick and Michonne, it took relatively little time at all for trouble to start brewing between the two, as evidenced by their current sleep positions. The way actress Danai Gurira talks, it sounds like problems will only multiply and worsen in the near future, and the blame can be placed on the way Negan's rule has neutered Rick's leadership. Here's how Gurira described Michonne's biggest challenge at this point in the show.
Those are quite strong words, but completely justifiable ones, of course. No one wants to see another person or group force their way into what was thought to be a safe haven, and then have them take supplies and weapons that everyone worked so hard to attain. Michonne showed audiences how much it's getting to her through her walker target practice, and how she kept it a secret from Rick. (Tension!) We later saw it again through her unwillingness to just hand over her rifle for Negan to confiscate. (It was originally for the Saviors anyway, but that's post-apocalyptic semantics.) She wants action, and not the nude and horizontal kind.
It's in Danai Gurira's explanation of why Michonne gave that rifle to Rick that it becomes a lot clearer how the faultlines in their relationship may not survive the current state of things. Explaining that she understands Rick is feeding into Negan's fear-mongering and guilt-inciting methods, here's what else Gurira told AMC.
After spending a lot of quiet time on her own, Michonne joined Rick's group partly because of the strength of Rick's leadership and survival skills, and she has been a part of horrifying situations ever since, with the main mode of response to threats being "retaliate." Watching a partially defeated Rick walking around has to be a strange and draining experience for Michonne, who only wants the group's usual sense of urgency to return. It doesn't necessarily make him unlovable, but emotions get weird when power and respect come into play.
Hope definitely sprang up again at the end of "Service" when Rick made his big confession, which worked to reverse some of the trust issues that were building up. But while she told Rick that she would try to stick with his plans, things obviously took another dark turn when Michonne came across the pile of burning mattresses. We'll have to wait and see if Michonne's love for Rick, and Carl and Judith, can outlast her yearning for a vengeful response to Negan and the Saviors.