What's the best way to breakup with your girlfriend of years?

Been with my girlfriend for 5 years we have 2 year old son, but Im no longer attracted to her.

I've been seeing this other girl which i'm falling for, we in the talking/flirting stage and she knows I have a girlfriend and a son Im very upfront with her

But I don't know how to end my 5 year relationship with his wonderful human being without hurting her , she hasn't done anything bad, it's just i'm not attracted to her anymore

Any help?

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+1 y
We have officially broke up.
What's the best way to breakup with your girlfriend of years?
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