Yes, but people regularly hear "oxycodone" whenever I mention oxytocin, which is disturbing. The mental association should not be "a-ha drug!", it should primarily be "oh, he's talking about the love hormone."
Your mental association is "love hormone." Nowhere does that mean it
should be "the love hormone." Oxytocin is a hormone and neuropeptide involved in dozens of known and more unknown functions. Most of them are bodily stuff and not notedly psychological. Some of the psychological stuff is very unloving, like a positive correlation with oxytocin levels and rejection of outgroup members.
Love is a complicated process involving a lot more than oxytocin.
Personal heuristics don't translate to building blocks of information. Personal, simplifying heuristics, even when true, don't mean that other things therefore are not true.
No hormone or neurotransmitter is the "love" or "background" hormone. They aren't one thing, and the things they are don't neatly align with our language in such a way that their causes and effects can be reasoned as such.
Your experience with SSRIs may have been general emotion muting. That's not uncommon, but that's personal. It's possible that if you're experience significant blunting, it's because your dose is high enough to significantly downregulate your receptors. That would mean your mental association with the effects of adding serotonin comes from a personal experience of, long term, decreasing serotonin.
MDMA's euphoria isn't fully understood but the best evidence suggests it comes primarily from the flood of serotonin it releases. If it was significantly the dopamine rush, that would make its effects more akin to amphetamine or cocaine. If one is taking a high SSRI dose and has downregulated serotonin receptors, most of the euphoria effect of MDMA is blocked. That's a good clue the locus of euphoria is not in its dopaminergic effect.
But the thing that really irked me is that GoodSarmatian was riffing off your comment and even if your response was correct about what oxytocin is (it wasn't), he demonstrated an understanding of what you meant and you in turn responded back to him as if he didn't.