My situation is similar to Shelley P. I am a single parent who chose adoption. I do believe that the ideal family situation is a married father and mother. Therefore, creating a life knowing that I could not provide that was not the right choice for me. However, I also knew that I could provide a stable, happy family life for a child who did not have family. My daughter is way better off with me than she was living her life in an orphanage, so that was the best option for me. If your sister feels that artificial insemination is the best option for her, then so be it.
Would you feel differently if your sister had sex to get pregnant? If your sister merely wanted to find a partner, she most likely could do that as could almost any female seekingto find a partner. The thing is that your sister hasn't found the RIGHT partner yet. I also had not found the right man to marry. From my own perspective, it made no sense for me to miss out on the joys of motherhood merely because I had not found Mr. Right by a certain point in time. Try to consider it that way...if your sister has all these great qualities and the wherewithall to become a mom, why should she have to miss out on it? As punishment for not finding the right mate? Anyone can find someone with whom to procreate, if that's the goal, but it wouldn't necessarily improve her future family situation as a single mom. It could create a lot of headache with custody and shared decision making with someone that she would not have chosen to have as a permanent part of her or her child's life.
In regards to single parenting, anyone could become a single parent at any time whether by choice, divorce or death of one parent. There are no guarantees for anyone that they will not be a single parent. Parenting alone is undoubtedly hard work. However, your sister is going into it more prepared than most as she is planning to become pregnant and as she knows that she is going to be doing this alone. She his aware of her finances and career situation and has had the opportunity for as much preparation as possible. Also, I think that for insemination, as with adoption, that single parents are typically required to have some psychological testing and counseling prior to the process to ensure that they are approaching it for the right reasons, with the right expectations and responsibly. This is not something that is rushed into. Your sister probably doesn't realize exactly how hard single parenting will be (I didn't), but that does not mean that it is not worth it, that she cannot do it and that she will not love it. It just may be harder than expected. And, it also means there may be more opportunity for you to help out with her little one if you would like and to develop a strong bond with your niece or nephew.
Truthfully, I might now want to know about all the details and proceedures involved in insemination, but I feel that way about anyone's pregnancy. With anything involving the body, there is such a thing as TMI. So, perhaps set up some limitations with your sister to avoid the details that cross into being TMI.
As far as not knowing the father...my daugher rarely asks about a dad. She knows her friends have dads and that she does not. It's more confusing to my daughter that she didn't grow in my tummy. She understands that God makes all kinds of families and that the world would be boring if everyone were the same. God didn't give her a dad that we know, but he gave her a lot of people who love her very much. She'd probably like a dad someday, but for right now, she doesn't really like the idea of sharing a mom with anyone else.
I think your sister will be fine. After the baby is born, you will probably feel a lot differently, as well.