SLAA perspectives on open relationships / ENM?

My boyfriend (46M) and I (F26) am struggling. He has cheated on me again. He is a serial cheater who lies and craves he validation and affection and validation of multiple partners at once. He is most definitely a candidate for being a SLAA himself.

I am quite sure I am a SLAA. I very quickly fell in love with him and I’ve struggled with obsessive, controlling behaviour, manipulation and jealousy.

My love for him is unwavering and I am not ready yet to let go, despite friends and family urging me to. However, I can’t imagine my life without him.

I am thinking of proposing the idea of an open relationship with him. One where I am the primary partner and his primary focus. However, as long as I am being prioritised fully, he can do whatever to cope with his struggles and pains in the side. Perhaps, even, giving myself the opportunity to be aware of his cheating might release me from the need for controlling, which gives me excessive stress. Perhaps this will be healthy for us.

Are SLAA people against open relationships? Am I overlooking something? Any advice?