Pacts and infatuation

I don't know if anyone else has struggled with this, but in my past relationships infatuation/obsession whatever you want to call it, was also closely tied to my ideas of sui. Like a few years ago I was in this relationship that was extremely unhealthy by normal standards due to my obsession, and this is one of the reasons me and that person split up, well, during that time I was constantly thinking of making a pact with them. It was almost as if my idea of "love" was tied to them and their survival.

In other words, if they disappeared with me, it would mean that we were so closely tied together-even in death. Don't know how else to put it.

Anyways I say all this because I don't think I've witnessed sui pacts IRL even in the media I consume, so I don't even know where this idea of a pact being "romantic" came from???

Anyone else have a similar experience or thoughts?