Any advice for a childless step mom?

My fiancé has two kids, I am however just a dog mom. I’ve gotten along very well with his boys, since the first time we met. They told me they love me the third time I met them. The oldest even started calling me mom, after our fourth time meeting. I love my fiancé and he is absolutely the best man I’ve ever dated. However, I am beginning to have second thoughts. He never told me how much baggage came with his ex wife. She just got arrested for the millionth time for drugs, to say the least. She is basically a crackhead, and has chosen drugs over her family. My fiancé has a court case coming up to fight to get full custody, which has been stressful for both of us. The children currently live with his parents because he is active duty military. We brought them to our house to stay with us for a month for the first time, over the holidays.

Something has shifted in me throughout that time. It’s like reality has sunken in, and I now know just how drastically my life will change once they live with us full time. I don’t know why, but I have some feelings that are not the best. If I am being honest, I don’t want the responsibility of being a step mom. I absolutely adore and look forward to motherhood, at the right time. I’ve been very responsible with my body, to not have children until marriage or until I’m ready. Am I selfish for not wanting the responsibility of the step children? I feel that it is not fair to me. If I wanted children by now, I would have them. I am saving all my sacred love and precious moments for my children. I guess what I am asking is to hear others stories. The stories of fellow step parents and step children. Something to give me hope, or the truth if I need to leave this situation. Please feel free to ask more questions, I can only type so much on here.

Any advice for a childless step mom?
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