OK.
Are you willing to kick them out? At their age the mates around on a weekend is something they won't want to stop. Would you rather she is close to you so you know she's OK, or do you want her gone again.
Are they paying their way??
All I can suggest is that you tell them to pick up their act, or move out. If they don't want to go, they won't really have a choice if you go - if your house gets sold.
I don't really know what else to say. Are they both working & going to work every day? If they are & are paying their way, I have to tell you that they aren't too bad.
DH & I moved into the caravan at the back of my mum's place when I was about the same age. I wasn't working - I made a half hearted attempt to do a TAFE course to keep mum off my back, & DH went to work when he felt like it. We didn't really pay our way. We didn't really have people over though either. I think we were too wrapped up in each other.
I think if they are at least doing those things you aren't doing too bad. They are showing a bit of responsibility. I know leaving on the lights on & using the dryer is a pain, but it could be worse.
Are you getting along better with her?
Maybe you could give them 4 weeks too pick it up - they will have to learn to do these things themselves anyway. Then maybe start by telling them they'll have to start paying the bills, or doing their own cooking if things don't change.

Good luck. I really hope you can work this out.