MIL issues

Okay so I'm gonna clear something up real quick, my SO and I are both teens ( kind of) he's 18 I'm 16, I live at my moms house and he ( kind of) lives at his moms. No before you comment stuff like " oh well don't be ungrateful she let you stay at her house" keep in mind she wanted us here, we were going to go stay at my dads but she wanted us here so we said why not. The reason we aren't in our house yet is because it takes a very long time to buy a house ( currently on month 4) and on house 4 months we've been back and forth from my moms/ dads to his moms house ( his parents are still married mine aren't) they like to go on spontaneous trips like camping and cruises and what not so they never let us stay here while they're gone ( it's because we're not married, we can't even sleep in the same room) well his past week they left to go on a camping trip and when they came back his mom said she found a cigarette wrapper?? We cleaned the whole house before they came home (which they deciddd to cook a steak dinner for only them two and my SIL and leave us the mess the night before they left) and now she's saying we're smoking weed in her house?? She said " next time we're gone y'all are not staying here" like okay? If y'all were gonna make all these rules why even insist on us staying here? We haven't done anything wrong and we've never smoked not even a cigarette here. On top of that she's really pressuring us to get married and I told her I wanted to wait until I could have a big wedding & she said " y'all can just get married here and have the papers then have a wedding later on" like ??? She only wants us to get married because she's super religious and she's not comfortable with us living together without being married. Like I'm sorry if I'm being dramatic but I'm not going to get married without a wedding, the whole point of a wedding is to get married with all of your friends and family. Also, they don't pay for ANYTHING for us. They pamper the crap out of his older sister ( who is older than him) we buy our own food, we pay rent here ( crazy right? They insist on us staying here because they "want us here" aka pay rent) we literally bought our tv. I'm not being ungrateful, I have a totally free place I could stay we arent depending on them in Amat way. We do so much for them and get nothing in return. Am I being dramatic? Should we just stay at my dads house until we get the house? ( all of our stuff is in a storage unit)