Confuseddad, can you give some more details? How old are your kids? Does your GF have any children of her own? How much responsibility does your GF have in terms of caring for your children (i.e. cooking, cleaning, transportation to school or activities, financial impact on her, etc.), either because she has taken it on as the "woman of the house", or because you have asked her to? What is the nature of the communication between her and your kids? What is your ex-wife's (I presume she is your ex-wife) role in the kids' lives?

First and foremost, speaking as a stepmother--heck, just speaking as a WOMAN-- do NOT tell her her feelings are off base.

That has been a revolving argument with me and my DH--him telling me I am over-reacting, or that something doesn't matter, I'm making a big deal out of nothing, it's not that bad, etc.

Feelings are FEELINGS. Sometimes they cannot be helped, they have to be worked through. For me, there's nothing worse than my husband telling me my feelings are wrong. I feel invalidated and I HATE that.

My DH's ex, my SS's mom, has caused A LOT of drama for us---nasty court battle, physical assault, drinking, problems for SS, etc. It's been rough. But the thing is---my husband is used to her behavior. I am not. And it wasn't "normal" or acceptable to me. He didn't think stuff mattered---I did. And we fought BIG TIME, mostly because I felt completely invalidated.

I even told him at times that the situation made me resent being in a stepfamily at all. And his response was "that's an awful thing to say, to think or to feel." Like I was a BAD person for feeling that way.

Unfortunately--we cannot always control how we feel, but we CAN control what we do about it. THAT is my motto.

There are still plenty of times I resent BM's presence in our lives, I resent the schedule changes and inflexibility that comes with shared custody, etc. I feel unhappy about the impact it has on our life. And it is OKAY to FEEL that way.

I do not ACT on those feelings, though. I try to find where they're stemming from, and I work through them--usually, once I allow myelf to feel whatever it is, and work through it, the feeling dissipates.

I suspect---without knowing more details---that your GF is feeling overwhelmed and taken advantage of. Being a stepparent is HARD WORK. You [can] have all the responsiblities of a parent---carpool, laundry, homework, housework, etc---but without the privileges or even benefits. It can feel awful, particularly if one feels taken advantage of.

I, too, would like to know more specifics to your situation---how did this custody change come about, is your GF in a caregiving role for the kids a lot, how has it impacted her life financially, etc.

This comes with the territory, and one should NEVER be with someone with a child---even every other weekend---without thinking "How would I feel if this child[ren] was with us all the time?" Circumstances change ALL the time, and the dad who has every other weekend could--at any day--wind up with full custody.

I'm wondering if your GF simply wasn't prepared for such a huge life change and that's what's at play now.

Your children have been uprooted & tossed into a new home with a "new mom" & you think everything's rosy & you don't want to hear otherwise:

"she has gotten it stuck in her head that my children hate her, which really the opposite is true. So we have had alot of arguements in which she says that she is tired of trying to be the good step parent and just ending up hated for it. She has it cemented in her head that my kids hate her"

stuck in her head
the opposite is true
cemented in her head
feelings off base

Offering your spouse very large dollop of simple respect might do you both a lot of good;
this woman has been dropped into the deep end of the pool, she's flailing around, she's drowning, & the lifeguard is telling her it's all in her head.

Even if you've asked your children how they feel, odds are that they've told you what you wanted to hear.

Stop talking & start listening.

Listen to your wife (you remember, the person who's supposed to be your partner & whose partner you're supposed to be?), &
listen to your children, especially when they don't know you're observing.

I'll bet you'll experience some illumination.

I sometimes think SD21 does not like me or does not like the fact that SO and I live together. i judge by the things she does. She does little things that are upsetting like always takes my stuff without permission or constantly shows me her mom's pics or talks about her mother 24/7.

like recently she insisted I look at the picture of her dad and mom in their 20s. what for? Her mother is objectively very unattractive woman, she looked like man then and looks even worse now, looks hideous next to her dad. it is a really bad picture. so there is no way she showed it to brag how great is her mom. i think she showed it to annoy me. I didn't even know what to say. what do you say on something like this? 'wow, your mom was even uglier then"? I mean seriously? and her mom left SO for TOM, so why showing me her pics now?

My SO thinks she is just clueless. I feel otherwise.

"Her mother is objectively very unattractive woman, she looked like man then and looks even worse now"

HAHAHAHAHA. I'm sorry but that just made me fall over laughing!

What makes you so sure your kids don't hate her?

Serious question --

lovehadley, hahaha I know...I am not being mean, but it is true, hahaha she actually looks a bit better now as she got older. when she was younger she looked like a very rough man with a military hair cut wearing a dress. hahaha no matter how she looks I just don't know why SD21 insists on showing me her pics all the time. I saw her in real life and it is bad enough. haha

once SD's best friend was over and SD called for me all over the house to show me once again her mom's pic and a pic of the house when mom and dad were married. SD's friend looked at SD terrified and asked why are bothering PO1 with all these pics? good point.