They still want a relationship with that person but an ex is an ex for a reason and people forget that too much often . And also when a girl or a guy jumps in and back in a relationship that's not a good start, you want a stable patner.
If this happens, I assume your gf/bf realized where they went wrong and wants to make things right by trying to get you back. With this, you have to be REAL careful & keep your eyes open for anything.... Has she cheated on you? Is she shady about things? Think through all of these things and depending, you can either take her back OR leave it hanging... From your photo, you're gorgeous, never chase after relationships, it'll always backfire! I'm going thru that now :( Email me anytime for advice: firstname.lastname@example.org :) I myself want a long-lasting relationship!
it honestly depends like why she broke up with you in the first place? and it also depends on why she wants you back. like if didn't work out between her and some other guy.! i would say NO! dont go for it because she obviously might do it again and hurt you in the process.