It could absolutely be a side effect of the antipsychotics.
For me, some antidepressants cause me to stop crying. Also the antipsychotic aripiprazole (it's the only antipsychotic I've been on, so I can't comment on others) caused me to stop crying.
Fortunately, I was only on it for a bit due to other bad side effects, and don't have a psychotic illness, just had an unexplained psychotic episode.
Is this specific side effect bothering you a lot? If so, I'd suggest bringing it up to whoever manages your care, and try to stress how important crying is for you. They may be able to sort out a solution like lowering your dose.
Edit: Just adding that it's really important your frustration doesn't cause you to do anything drastic, like discontinuing your meds without medical supervision. This could cause very bad consequences.