step parents

I'm having trouble being the other women.   When there son has family events and mom and dad do things as a family I feel left out.  Like I don't mean shit!  I'm so lost what do I do?   Having an anxiety attack right now..  I've made these people my world..   Our relationship is severely complicated I feel like I'm losing all control and she basically controls him.   He loves me he says he loves me and I don't have a child so I wouldn't know but things just have to be different.  I can't always be involved?  I've looked up tips for being a step parent and there aren't much.   I need to let this guy go.   How do I do this alone? Please help 😭    I know I deserve more..  I deserve a man that shows how much he loves me.   He used to be all about me.  We have broke up many times cuz of this women wanting to work things out with him..  It never works and we get back together.    But he is different this time.  He isn't the same man I fell for