I’m a non married mother. Boyfriend and I are still together. We have an infant. My son and I are on Medicaid. We agreed that I could claim my son this year. Need help.

Basically I’ve been living with my boyfriend and his family. I paid two months rent because that’s all I could afford. The mom wants to claim me on her taxes even tho I am 18 soon to be 19. I filed for my taxes this year and claimed my son on my taxes. I have Medicaid. Do I need to share that I have Medicaid? I’m so lost please help