Being Friends with Exes

How do you guys feel about your man being reachable by his ex to a point where she calls his phone every day 2-3 times a day. My man claims they’re not friends and that she’s basically just obsessed over him, he hasn’t answered the phone or been in contact with her since we’ve been in a relationship but I feel otherwise. Because no woman is going to blow you up or chasing you down unless you are giving her a reason to. At first I was trusting that he was handling the situation until earlier last week when she called and I answered the phone, she asked me who I was and I said this is his girlfriend! She cursed me out and then drove two hours to his home looking for me to try to fight! Am I wrong for feeling like it’s more to the story or do you guys see what I see?