There are several sources which say that our spouse is predetermined from when/before we are born. I remember hearing a Rav say once that there are many people who we could be equally happy with as our spouse, and to choose someone and focus on making it the right choice after, which seems to contradict this.
I have noticed that the idea of a bashert often seems to be used quite negatively - e.g. a single person may think "is this my bashert?" and be perhaps too restrictive in their parameters for who they consider for a suitable spouse. Similarly, I think that in marriage, some people think "is this my bashert or did I marry the wrong person?"
I wonder if this is not what is meant be the idea of a bashert though and we are missing the point, and that accounts for the idea that we could be equally happy with many people. I suspect that the point is that we should try to think of our spouse as "this is the person who Hashem has decided should be my spouse" and that it should be something that strengthens our marriages, not weakens them. Obviously, this only works to a point and I'm not talking about assuming that in an abusive marriage or where a couple are clearly such a bad match that continuing the marriage is clearly a bad idea.
Practically, I suppose that the point is that we should not assume we know who our bashert is until we are engaged, and from then on to assume it is the person who we are engaged/married to.
Is this an idea that anyone has come across before? Is there a source for it? Are there any alternative ways to look at the concept that I haven't covered?