seriously. it's not that big a deal. if people in gaza are still standing up to their oppressors every day then you likely have zero excuse for not doing more IRL shit (political reading and writing at home are good, but don't mean anything if you're not applying that theory as practice and then assessing the results and adjusting your practice accordingly).
dating within an org is only a problem when more influential members date less influential members, the representative of a local chapter probably shouldn't start dating one of their members, it creates an imbalance of power, this isn't limited to socialist orgs though, it applies to any organisational structure.
I think this, and also your org needs to be large enough that it isn't dominated by a couple of de factor power players (it's easier to police official positions with power than someone with a lot of social clout). Otherwise any drama just kinda nukes the org.
Yeah, small orgs need to have a very strict barrier for entry, to avoid wreckers and drama, but also need to avoid having a small group form the "core" of the org and decide everything through seniority. I will freely admit I'm not skilled enough at people management to organise an org from scratch like this.