Relationships

How to break up in this instance?

Boyfriend and I have been together for one year and half. Our relationship has been great until recently. He has a son with autism so I have been taking care of him whenever needed. I watch his son at the baby's mother house. Which has been a nightmare. For starters she told me that there are not together and have not been intimate in 10 years. But I've notice little tactic she does around the house. She watches me on camera which is extremely uncomfortable, she purposely comes home late when she knows I have to get up early for work. She also try's to put me against my boyfriend. It's like she's nice to me when he and I are fighting. But mean when she knows we are in a good spot. I don't think she wants to be with him I think she just doesn't like that he's happy with me. Her mother moved in town and she basically told me that neither one of them had their kids for 5 years. Which is explains why the Mother threw their child off on me once I started coming around. She also mention they are still legally married but have been separated for 5 years , and she keeps asking me what am I to my boyfriend. I've confronted him about this and he says he does not want them in our business because it never worked. He has a younger child by someone else and he claims they were the reason it did not work out. Which I understand base on what I'm experiencing. We have assets and a business together. I would've never got involve if I knew he was still legally married. I'm trying to figure out how to release myself from this mess. Any advice on how to get out?

How to break up in this instance?
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