An Unusual Proposal

I'm not sure if anyone will read this, but if they do, I am new to this site, and am looking for some guidance/advice, and would welcome an considered response.

I am a straight woman in my mid thirties, and have found myself in a perplexing situation.

I am very much in love with my boyfriend. However, he is significantly older than me, and has an adult daughter who may or may not have a horrifying genetic disease (we won't know till she does genetic testing, which she is unwilling to do right now.) In any case, he is staring down the barrel of a great deal of responsibility concerning his own child. Although is has been a sad decision to come to, we have decided that it isn't prudent or possible for us to have a child together.

That said, we want to stay together, and I still very much want to be a mother. I have been considering just going to a sperm bank. However, I have some discomfort about this because I do want a child of mine to have a present parent, even though my boyfriend is willing to act as a step parent of sorts.

So what I am interested in is perhaps having a child with a gay man/couple. I am not really proposing surrogacy because I would want to have the bulk of the custody. But I would also want to share custody so that a child might now his/her biological parent.

What I am talking about, in essence, is the creation of a non-traditional family unit, that would allow me to have most of the custody of the child, but also allow a gay man/couple to parent said child on a part-time basis. It would mean weekends for the man/couple, weeks for me, and possibly, if we could all become friends, even forming a family unit in which holidays are celebrated together, etc.

I wish this could come about more naturally, i.e. through friends but I have just moved to a new city, and so my friend network is a little underdeveloped.

So does anyone out there know if this ever happens? This formation of non-traditional families? I would be really interested in any advice or information.

It is a tricky business. It is a bit like shopping for a mate through a personal ad, except I am shopping for a father for my baby. Obviously, I would want someone or a couple who would share my values and beliefs, particularly in terms of parenting. But I am also looking for a man or couple with whom I could become attached and could enjoy sharing this experience with.

A little about me--I am highly educated, and am in a city on the eastern seaboard. I am very gay-friendly---my boyfriend's daughter is bisexual, so we already have that aspect in our family life. I am in the process of embarking on a second career as a pediatric nurse, but spent the earlier part of my career as a preschool teacher in a non-traditional setting. So, I have a great deal of experience with children and parenting.

In any case, if anyone knows anything about whether such arrangements are ever made, I would be interested. Although I would like to have this take place in my city, I think person is more important than location, and for the right man/couple, living in a different city would not be a barrier.

Thanks.