Help! New full time stepmom

[SAstepmom5]

I am writing this in desperation. I have been with my wonderful partner for 3 years and am about to marry him next year February. He has full custody of a lovely 12 year old girl. The birth mother sees her maybe for a couple hours every few weeks. He and the birth mother never had a relationship. I get on very well with his daughter, lets call her L. She loves and respects me as I do her. I couldn't ask for a better relationship with her.
The problem: We have been slowly moving them into my place so that L can adjust and feel comfortable with it. But I'd say they have been living permanently with me in my 2 bedroom flat for about 6 months now. I had to make some major adjustments and get rid of a lot of things but we are making it work. He works full time and studies part time and only gets home around 7 in the evening. My hours are more flexible and I do some work from home, and I am also studying part time. Because my hours are more flexible I am able to fetch her from school, take her to extra murals etc. But because I am with her for most of the day and he isnt I feel like the primary parent and its overwhelming. I have to fetch her, make sure homework is done, shes showered, take her here and there for this book or that project, help with homework, discipline her, get dinner going (she has recently decided that she is vegetarian, so thats also now more complicated and time consuming) all on my own.
I feel like a baby sitter and dinner maker and thats it. My partner is very busy so I feel distant from him. I just feel overwhelmed in my new position. I feel guilty as I have started to resent them both. Is this just what being a mom and wife is? Must I just suck it up and deal? I have zero experience in both fields so any advice would be greatly appreciated.

You have basically been given the position of mother without this being properly asked or discussed. It is a huge thing to be a mum, and for a step mum even harder, as you don't have the benefit of knowing the child all your life. No wonder you are feeling overwhelmed.

I don't think it is fair of him to put this onto you at the moment. If he's not back until 7pm then he is not there for most of the child's week. My DP also was not back until 7pm or later and I had a DSD.

Youre right, I shouldnt be the only one making sacrifices. I cant have children so no fear of having a baby now.

Thanks for everyones feed back. I will chat with him this weekend. Hopefully all goes well and I dont lose my nerve.

He needs to compromise - this is HIS daughter and he needs to take responsibility.

He is just merrily getting on with his life whilst expecting everyone else to do the donkey work and I expect he is only too happy to take the credit.

It's not fair on you.

I'm in the same situation and it's tough OP, have turned into full time carer for DSD 7 now DP has got a more demanding job. I have also have a DD and a full time job. He needs to step up - had numerous discussions with DP and any times I say I need my own time and space from her it's seen that 'I don't want her there'. No, I just don't see it fair he can progress his career and have hobbies when I'm looking after his DD for him. Anyway, just be prepared that she will always come first. Make sure you've got your own life too.

So just thought Id update everyone.
Had a long chat this weekend and I feel we made major progress. We cant afford extra help so I will continue to pick her up from school. She will stay at aftercare at school till around 3/4. The changes we have decided on is we will have one dinner or lunch a week just the two of us. DSD will either stay home alone or go to her gran. If we go somewhere just down the street I think she will be ok on her own for an hour or so. We have spoken to her about this and feel honesty is best, and she is old enough to understand that we need a little bit of adult time. She seemed to understand and be ok with it.
DP has promised to be more present on weekends and do the dinners and shopping on the weekends. And although he is very busy with studies I've said to him that that doesnt mean that he can only focus on that when he is home. He needs to play a larger more interested role in DSD life. He agreed. I am so glad that I spoke to him as I already saw a huge difference this weekend and Im hopeful that it will continue. DP is also very happy about me finding this forum as none of my friends have children or are in a situation like I am, so thanks to everyone for your help and feedback.

I think I should also mention that he does not have a whole lot more parenting experience than I do and we are both just figuring this out. Its a complicated story so I'll try keep it short:
He had a one night stand with a woman he didnt really know, 6 years later she tracked him down on facebook to tell him he had a daughter. She had previously told her ex boyfriend it was his but when they broke up she contacted my DP. He had paternity tests done and she was his. He only met her for the first time when she was 6. He was as active in her life as he could be at this late stage. But still only a weekend dad, and had to work slowly at getting to know his daughter and gain her trust. When DSD was 9 I met my DP and a month into dating we found out that the birth mother was using drugs, thats when he managed to get full custody and has had full custody ever since. So DP has had to make many changes and I think like me he is also just trying to figure things out and make it work. DSD has been through a lot too but has this inner strength and in spite of her difficult past she is turning into a lovely young girl.
At the end of all this I have learnt that communication is key and if I dont say what is bothering me, like many of you said I should, he wont know and we cant work on it.

That is a lovely update, SAStepmom - so glad that you've had a productive chat and some positive changes have already taken place! Best of luck for the future, sounds like you're all willing to take steps to improve things, so that should make it easier to get all your lives on track together.