I'm reeeeally not trying to be a jerk here but frankly you need to grow a pair and lay down the law. If she wants to have a date over they can deal with you doing what you want in your house. Frankly I would've gone off on her about getting a tattoo before rent. She's acting like a spoiled child and she need to grow the freak up. I would personally lay out a plan in writing with her of the exact amounts and dates of payment expected of her now that she is earning an income. Also some house rules. If she violates these you need to treat her like any landlord would and give her a notice that she needs to pay up or get out. In essence quit being a pushover, I understand you're trying to be nice but she's walking on you.