Well, you really only have once choice here and that's to move. She's not going to leave you alone on this. She's too into her religion and will not respect your rights to yours. Bottom line she has the deed to the house, financial issues aside, and that means she can call a locksmith whenever she wants and repeat this disrespectful little maneuver any time she likes. Now that she knows her kid is married to a witch she's not going to be happy until you are divorced and her kid has sole custody and you are cut completely out of your daughter's life. If your SO won't stand up to her you don't have much hope of this relationship lasting. Seriously, people like this never stop. You're now public enemy #1 to her and too dangerous for her kid and her grandkid to even be around. You could try educating her with some reading material but I doubt it would make a difference. If it were me I'd say "Screw her and her finances." and move. Let her fend for herself and see how well she does. But that would require your SO to get a backbone and to back you up on it. If he won't? There's probably nothing you can do until you can change your living situation. I've known several people in your situation. Almost every time the ultra religious MIL used the situation to get the couple broken up. The only time it didn't work was when the partner who was their child supported their partner and stood up for them and told the MIL to stop OR ELSE. You need that support in this situation or you're likely going to have nothing but trouble with her and this scenario will likely repeat itself. If she's that dead set against Wiccans she's likely going to do anything and everything to split you up and to see to it that you lose any hope of custody to your own child. You can't trust her, not one bit. Basically it comes down to one of two things. Either you have to move out now while you are still a couple and find your own place or your SO has to absolutely lay down the law and support your decision to worship as you please and stick to saying it. If your SO won't? You might have bigger problems than your MIL...