I (F39) discovered I was the sperm donor child and my husband (M41) accused me of cheating

When I was a teenager I noticed that I didnt resemble my dad much - no similarities, no phenotype matches. I asked my parents and they said that I was the result of a sperm donor. They said that my dad was sterile and that it was hard for them to conceive me. I grew up with this knowledge and never really thought much about it. When I was engaged, I told my fiancé (now husband). <br><br>It wasnt until I was 25 that my interest in my donors ancestry came to light. I did a DNA test just for fun and found one match - a half sister. I reached out to her and we discovered that our donor (my biological father) had fathered 52 children via donor sperm. I learned that he was a prolific donor between 1990-2000 and that he was black. I learned that I am biracial and that my dad wasnt my biological father. Again, I shared this info with my husband, telling him I dont see this man as my dad, and that the man whos name is on my birth certificate is and forever will be my father. He was very supportive. <br><br>Five years ago when I was 36 I was worried I was running out of time to have kids and decided to do IVF. I learned that my husband was sterile and that his sperm would not be viable, that we needed to use a donor. A month later our beautiful baby boy was conceived and is now 4. <br><br>Last week my four year old cut himself and needed stitches, so we took him to the ER. While there the triage nurse took my sons DNA using a buccal swab and compared it to my husbands DNA using the same method and confirmed that my husband was not my sons father. To confirm, a few days later we did a paternity test which came back 0% and the lab tech concluded that my husband was not my sons biological father. My husband was furious. He accused me of cheating on him and that my son was not his. I tried explaining how the donors sperm was used, but he didnt believe me. He said he wanted a divorce and left the house to stay with his brother. <br><br>I am at a loss for what to do. My husband wont answer my calls or texts and Im just worried for our future and my sons future. What can I do to prove to him that I wasnt unfaithful?<br><br>**TL;DR:** I (F39) discovered I was the result of a sperm donor and when my husband (M41) and I decided to have kids we also had to use a donor. When our son (M4) needed stitches the ER did a paternity test and discovered my husband was not the father. He thinks I cheated and wants a divorce. IDK what to do.<br><br>EDIT: Talking to a lawyer as well as my husband right now. I have all the IVF papers, donors sperm information, our communication records and the whole shebang. He is getting over his exs divorce and needing time and space. <br><br>The half siblings have been following along this whole time lol. I told them dont you dare say anything until this is resolved, and they obliged. <br><br>Me and son are staying with my parents, brother and SIL. Threats and angry messages have been pouring in, but theyre all on my husbands fb friends list.