What's it like to be quarantined with a significant other? I wouldn't know. But based on how annoyed I've been with my upstairs neighbors (for walking around), myself (for existing 24/7), and my houseplants (soooo needy), I can imagine sharing a roof with an actual human for weeks without respite can take its toll even on the healthiest of relationships.
Luckily, the internet is a great place to vent. It's not like it's public or anything.