I don't even know any more

All I ever wanted was to be a mother! Instead I'm a stepmom to kids I love dearly and do everything for but they hate me and walk all over me and tell me If I ever have a child they will go live with their mom and never talk to me again  :( I'm a good person! Almost 30 living 3000 miles from my home with my new husband just feel so alone! I want everyone happy I feel too old to ever be able to have my own family! :( I thought it would be easier. I do everything for my family!