So there are two ways to handle this, both however require you to stick to your budget and stop agreeing to activities without knowing all costs upfront.

1. You sit down with him and go over your income and how this spending is impacting you and if he still doesn't get it you leave

2)Skip step 1 and you leave the guy who clearly has next to no compassion for your situation, he calls you cheap and doesn't question anything? not a single can you afford this? or are you doing alright with money maybe I can cover more dinner or we can go to places we can both afford comfortably or hey here is this free thing to do.