Whoa! Wait a minute, you people saying, in essence that the husband and his new girlfried being shot and killed is his fault because he didn't end the relationship properly is like blaming a woman for being raped because of the clothes she wore. Regardless of how he ended the relationship she had no presumed right to kill him and the girlfriend because she felt slighted and betrayed.
My ex-wife and I had a MOSTLY amicable divorce but she is not welcome inside my home and I am not welcome inside hers. In fact in the 3 years since our divorce she has been inside my house exactly one time and that was when our youngest son was staying at my house and was very sick. The only time I was ever in her home was when my youngest was moving in there, I helped him move some belongings in.
Be wary of exes, even amicable ones...