It's been a very long time since I had an EX.  I've been married 22 years now.  Do you know much about those relationships.
I know the term can sometimes have a derogatroy meaning, bringing up unrequited feelings
Yes, I can see how that would happen.  I think many people may have issues due to past relationships.
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
a 2011 interview, White said that she always knew her close friend Liberace was gay and that she sometimes accompanied him to premieres. A supporter of gay rights, White said that "If a couple has been together all that time – and there are gay relationships that are more solid than some heterosexual ones – I think it's fine if they want to get married. I don't know how people can get so anti-something. Mind your own business, take care of your affairs, and don't worry about