An image of stepmothers I've been particularly focused on dispelling these last weeks as I speak to the media: empowered, evil excluders and victimizers. As any woman with stepchildren knows, and as the research so clearly spells out, our perceptions of who stepmothers are could not be further from the reality. The studies and anecdotal reports from mental health professionals who work with stepmothers actually paint a picture that will startle many: stepmothers are by and large the most powerless and vulnerable members of the stepfamily system.

Experts including Jamie Kelem Keshet have found that when a woman marries or partners with a man with children — particularly if she has no children or "mini-family" of her own — she must struggle to find her place, and often feels like an Outsider or interloper. Her partner and his children may not be much help here. He may feel too guilty to show his kids just how important stepmom is to him, and the kids, as Dr. Mavis Hetherington has observed, are often perfectly happy for stepmom to remain on the periphery of conversations and activities, fearful that she will replace them in their father's affections and the family hierarchy somehow if they let her "in."

Too often, a stepmother is subjected to stepchildren's hostility and rejecting behavior — something that is normal, but frequently goes unchecked for far too long (due again to dad's guilt and fear). If she adheres to mainsteam stepparenting advice ("Leave the disciplining to him; you be the fun friend, etc,"), the woman with younger stepchildren finds herself in a position of having no say about parenting practices in her own home. She may also find that both her husband and her husband's ex give her "responsibility without authority" — expecting her to pack a stepchild's lunch just the way he likes it, for example, but telling her she's crossing a line if she tells the child to turn the TV off.

The stepmother with older or even adult stepchildren is not necessarily exempted from this problem of lack of authority in her own home. Many women told me they had endured snippy remarks and barely veiled hostility from their adult stepchildren, often for decades, because their husbands' attitude was, "I want us to have a nice time when we're together, so don't make a big deal about it. Just let it go."

This disempowerment in her own home can have dramatic effects. A number of researchers have found that stepmothers are vulnerable to physical threats and abuse in their households: several women I interviewed told me older stepchildren getting physical with them by shoving or pushing them during an altercation. The recent murder of Kenzie Houk, allegedly by her 9-year-old stepson, underscores the fact that, in the tinderbox of stepfamily tensions, stepmothers can easily become victims, sometimes in dramatic and tragic ways.

Other than feeling like and being outsiders, having responsibility without authority, having little say over parenting practices or the rules of civility in her own home, and being emotionally and physically vulnerable, women with stepchildren have other profound vulnerabilities. Canadian researchers have found that, owing to their conviction that they must "blend" the family, and owing also to their fear of being perceived as wicked, stepmothers tend to take on the role of family counsellor and marital therapist, and to bend over backwards to be "perfect." The result is feelings of exhaustion and burnout. And such feelings, combined with the hostile environment she often finds herself in when the kids are around, prime her for anxiety and clinical depression (ample research shows that stepmothers suffer from markedly higher levels of depression than mothers).

Stepmothers might also find themselves in a disadvantageous financial position. The woman with stepchildren may be asked to sign a pre-nuptial agreement that essentially waives some of her economic rights as a wife under the law, or to contribute to child support and other payments. She may feel that saying no, or being assertive about matters of estate planning and inheritance will be viewed as "wicked," further undermining her ability to protect her own financial interests. Many women told me they felt pressured to contribute to a stepchild's school tuition, wedding, or travels in a way that was uncomfortable to them given the unreciprocal nature of the relationship over the years. Simply put, these women felt economically exploited by their husbands, their husband's exes, and their stepchildren.

And when it comes to wanting children of her own, the childless stepmother may find her husband or partner less than enthused, in spite of what was said earlier in the partnership. Finally, any complaints about her situation are likely to be met with suspicion and a lack of compassion, even by friends, who might say, "What did you expect when you married a guys with kids?" or "Why can't you just be nice?" The ignorance, judgment, and bias of others adds another layer of stress to the lives of stepmothers.

With Stepmother's Day coming up on May 17, I'm sure we're all hoping that we can begin to close the gap between the world's perceptions of us, and who we really are.