Bless your heart! You're probably so tired you don't know which way is up anymore. My daughter was similar to that when she was that age. Not quite as bad; but, enough to be a problem. You said that the little guy would cry for up to an hour before stopping. After that time, does he go to sleep? I understand the disruption his waking is causing everyone.
Is there a time period where you could allow him to "cry it out" for several nights, ie a weekend, holiday, etc? At 19 months, he's gotten used to using you as a self-soothing item. Now, when he wakes, that's how he gets himself back to sleep. Works for him, sucks for you! What needs to happen is for him to find another substitute for you for his self-soothing himself back to sleep. That process might take several nights of misery for all.
Basically, he needs help readjusting his sleep pattern and that's a trial for any parent. The only way you will get "to the other side" is to tough it out consistently (God, I hated that word when my kids were small) until he readjusts. You could also try introducing a "lovey" during naptime that he might bond with at night, as well.
Good luck to you all,
R. F.