If I made a new iCloud why am I pulling my old contacts?

Some how long time ago when I was with my ex, her contacts synced to my iCloud so I made a new one because I was so fed up with seeing her contacts with mine.

Today my phone broke and when I went to sync my contact on my new phone, again the contacts showed up!

How do I get rid off this!? It’s so maddening. Why does this keep happening if I made a whole new iCloud account?