I don't think theres anything weird about it. I think its great that you associated it to your ex. The way you described being overwhelmed is how I suspected my ex felt. For you it is real problems of having too much on your plate with no relief in sight. For my ex the problems to her were also real but for me I couldn't see it.
How does this insight make you feel now?
I feel like I understand him better. And I know the times he tried to explain it to me, I invalidated him. I took it really personally. I did eventually however, take the pressure off about the wedding. And he was the one that continued to reinitiate the idea of us getting married each and every time. I was learning to accept just being engaged... .and backing off... .but then he'd be like no, I wanna do it... .right now... .let's do it... .and so I was fine with that too... .but then he'd freak out again and act as if I had been pressuring him... .when it wasn't me.
I just wish that he could have not cheated and then after cheating... .not completely split the situation again. And when I asked why he keeps making our relationship so serious and all about marriage he said "That's where we are" I guess being together 3 years... .he thinks its either marriage or over... .and he went to be with replacement because he said she's less serious and new (kinda like a job outside of my field). I wish he could have found a way to take a breather inside of our relationship (because after all I'm not a career, I am a person). That or taken a break in a less destructive way.