<human>: My boyfriend and I have been in a three-year relationship and have been talking extensively about spending the rest of our lives together. Today, he informed me that in the past year, he's been discussing the possibility of donating his sperm to a lesbian couple he knows with the couple. He decided he wants to move ahead with the arrangement and be involved in the child's life somehow. 

I am in shock and I feel extremely uncomfortable, anxious, sad, and angry about this. My boyfriend never brought this up or asked how I felt about this arrangement. I don't know who this couple is and I've never met them, and yet I feel they may be a part of the rest of my life, along with their child. When I told my boyfriend I was very uncomfortable about this, he attacked me and said I was close-minded and that I should be proud of him for being kind and being "chosen" by this couple. I'm at a loss for words. 

What would you do if you were in my shoes? What are the angles I should be approaching this from and what questions should I be thinking about or asking? I feel so lost.

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<bot>: My long-term boyfriend told me he's going to donate sperm to a lesbian couple and wants to have a relationship with the child. I feel very uncomfortable about the situation and don't know what to do next.