Manipulation comes in a variety of flavors, from emotional to financial. It involves the use of something to control someone else's behaviors. The "something" can be intangible, as in the case of emotional manipulation, or tangible as with money. Some parents find it difficult to completely trust that they raised their children to be fully independent adults. These parents turn to manipulative behaviors, using guilt, fear or obligation, to coerce their adult children into making decisions they otherwise wouldn't make. If you happen to marry a person whose mother pays your bills, buys gifts or provides financial assistance in some way, such as allowing you to use her car or home, it makes for a difficult situation, but not one that's necessarily impossible to resolve.
Communicate your concerns to your spouse in a way that won't put him on the defensive. To do this, present your concerns in a factual, relatively optimistic and calm way that reinforces your marriage, according to a 2007 article published in "The Forum for Family and Consumer Issues," North Carolina State University's online journal. Express your concerns clearly, sticking to facts without inferring reasons behind his or his mother's behaviors. Imagine yourself describing a scene in a movie to someone who hasn't seen it; just describe what you see, not what you perceive.
Formulate a viable solution with your spouse to end your mother-in-law's financial control. The solution should depend on the nature of the manipulation. If, for example, your mother-in-law is paying one or several of your household bills, you might want to discuss a plan with your spouse to take back that responsibility. If necessary, create a budget to include the new expenses that your mother-in-law will relinquish. You might even have to get a part time job to compensate. Keep in mind that your spouse may have her own challenges relinquishing her financial dependence and your proposal to discontinue it may come with resistance. Dependence is often deeply rooted and is also a behavior that is learned from childhood. Be direct but not demanding in creating a solution.
Confront your mother-in-law, ideally with your spouse to demonstrate a united front. Just as you did in confronting your husband about his mother's financial manipulation, it's important to be clear about the boundaries you want and need for the sake of your marriage. It's also important not to waver in an attempt to "honor" your mother-in-law. Honor, doesn't translate into feeling obligated to let your mother-in-law cross the boundaries you set. However, you must set them. Don't expect your mother-in-law to recognize healthy boundaries. Communicate your boundaries by explaining the behavior you expect from her. For example, if she is contributes toward your mortgage payment, you need to explain that while you appreciate her help, you still don't want her stopping by your home unannounced whenever she feels like it. Explain that you want her to call first and that you need some time to yourselves.
Enforce your boundaries to stop the manipulation. Setting boundaries with your mother-in-law means drawing a proverbial line verbally and providing a consequence when she crosses that line. For example, if you tell her that you don't want her stopping by your home unannounced, but she continues to do so, you can ignore her if she enters your home, refuse to let her in if she rings the bell, or leave yourself. Be prepared to accept that she may tell you that if she is forced to comply with your boundaries that she will no longer provide financial help. However, if you reiterate that you simply need your privacy and will welcome her at other times when she calls first and arranges a visit, she might start complying with your boundaries.
Consider marriage and/or individual counseling to work through underlying problems that led to the manipulation. It's possible that if you resolve one manipulation issue, your mother-in-law might still try to manipulate you with money in the future by offering extra cash, vacations or expensive items. Counseling can help you avoid future manipulation, as well as help your spouse identify the roots of her financial dependency on her mother and reinforce behaviors that foster independence.