Quote From: mom2nandjI am step-mom to a wonderful 4 yr old boy, and have a 6 yr. old daughter of my own. Just for some background, I have been in my SS life since he was about 6 weeks old. Fortunately, he and my daughter get along great and view themselves as bona fide siblings, and my husband and I treat them as such. We share custody with his mother. We live only a mile apart, so my SS is able to have time at both houses each day.  
The problem is with ME. In the past, I had limited personal conversations with his mom due to the fact that we were going thru custody/child support issues and things were tense and uncomfortable. In the past year, those things have settled down, and she and I started being social with one another. Meaning, we would take the kids out on our own to do activities, and occasionally would hang out together without the kids. At first, this seemed fine. We are the same ages and have the same taste in music and social life. But after a while, I started leaving the gatherings either "mixed up" or just annoyed. I have been trying to put my finger on why that is. To begin with, we have very different styles of parenting. According to Dr. Phil's test, I am equally an Authoritative/Equalitarian parent, as is my husband. My SS mom is Permissive and parents out of guilt and wanting to be liked (she admits to this). So when we hang out with the kids together, I have to keep from trying to take over the mom role and do it "my way." He is so much better behaved in my opinion when I do it. I don't ENJOY feeling this way, though. Second, when things come up and schedules change, appts. are made and such, I have been getting so irritated if things have to be rearranged for his mom and her schedule. Our life is very settled, whereas hers is not. Working hours sometimes change and she is a full time student. There is always something going on. Sometimes my husband and I feel "on call" as parents.  
I just have a horrible feeling that deep down I am a bad person for feeling this way. I have tried to stay in the background and let my husband and my SS mom do the pick up/ drop offs, appts. etc. But they are NOT good communicators with each other. Plus, since I have been around from the beginning, it only feels natural for me to parent him and be involved. So to "butt out" feels unnatural. To her credit, I have never been left out, nor has she made me feel unwelcome in my role as his step mom. I just don't know why I am feeling the way I am. Could it be that I am not over all the arguments and issues from the past? Even those issues are nothing I have control over or can change. I love my SS, and I don't dislike his mother. Why am I having a hard time with this NOW, after 4 years? I know about good fences and boundaries and all that. But how do you go backwards as a friend, when you have stepped forward as one? If it were up to his mother, she would like to have one big happy family. So then I feel like a jealous prude. Neither my husband nor I are comfortable with the whole big family idea, though. (They were never married or in an "official" relationship-bottom line, didn't know each other that well). I DON'T LIKE feeling bitter and resentful towards someone who is so willing to make this work. Should I totally back track and keep things strictly parent to parent, or is there a chance we could be friends if I worked these issues out? Any advice?  
Its been 4 years, and you've got many, many more years to go! It is understandable that you would still have some resentment over past issues, but its time to forgive and forget. This woman sounds like she is truly doing her best. Have you ever heard the saying, "when you know better, you do better.." ? This saying applies to her. I'm sure it applies to you, too. It means we learn from our mistakes, as opposed to making the mistakes and then keep on making the same mistakes over and over.
You are in a position that millions of step mothers would love to be in! You are lucky but maybe you just don't realize that? You are living a situation that is, more often than not, a very tense one, but you are living it relatively relaxed. Perhaps you are uncomfortable because you think things shouldn't be going well between all of you? I just don't see why you can't relax and be flexible. If you are feeling "on call" .. well.. thats too bad, really, because as parents you truly are on call 24/7 whether you like it or not!
What is the relationship like between your daugher's father and your husband? Is there one? Perhpas the lack of that relationship effects how you feel about this relationship with your SS mother? There are many, many factors... but I think that the bottom line is you really have it made, and you should be happy for what you have. You are going to raise two happy and emotionaly healthy children, what more could you want?