Ever have an Ex you can't get out of your mind (for whatever reason)?
that depends, as a prefix ex can refer to a variety of relationships. 
True enough, let's say an EX, well not lover, but someone who you causally dated
I think most people understand that. As it is often used as a derogatory tinge. 
What do you mean 'derogatory tinge'?
Well, its usually not positive. sometimes its assumed to be a former romantic partner or spouse. 
Well, yes, in this case, it was a negative relationship as things turned out.
Ex (relationship)
In social relationships, an ex (plural is exes) is someone with whom a person was once associated, in a relationship or marriage. As a prefix, "ex-" can refer to a variety of different relationships; for example, one might refer to a music group's "ex-guitarist", or someone's "ex-friend". 
When used alone, "ex" as a noun is assumed to refer to a former sexual or romantic partner, especially a former
, and if that first idea is good then you are on the right track. It's not a sign of creativity to have 65 ideas for one problem, that's just a waste of energy. I also don't think you need to go anywhere particular to be creative; people just use that as an excuse. But I do think a lot of creativity depends on your relationships with other people, your personal relationships, your partner or whatever. Your personal happiness or unhappiness comes out in your work, it's