I have an ex that I wish I could see again, even though I'm with someone. I feel like a horrible person.
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
all about. Adele has openly discussed the genesis of it saying, "Well, I wrote that song because I was exhausted from being such a bitch, with 'Rolling in the Deep' or 'Rumour Has It' ... I was really emotionally drained from the way I was portraying him, because even though I'm very bitter and regret some parts of it, he's still the most important person that's ever been in my life, and 'Someone like You,' I had to write it to feel