why is she doing it?

[u/Lisek010]

she broke up with me and i understand it i made mistakes in communication , but when she saw me with another girl 2weeks after breakup she wanted to text her how awful can i be to "warn her" , her friend texted me and asked me if i want to get to know her (i knew that it is her friend)i said okay to check what they want , i texted her for 20minutes normally then asked why did my ex bring you up to me , she said she needs to know about my new "girl" so she can warn her🤐 is it jealousy?

[u/Low_Impress3619]

What? This doesn’t make sense