I don't have feelings for my girlfriend of 5 years, what should I do?

Long story short we been together for 5 years, she's a lovely girlfriend and respectful woman But I have lost feelings for her :( I dont get excited when I see her like I do when I see other women in public etc. She's been mentioning marriage for some time but I cannot marry a girl I don't have feelings for.

What should I do? what's the best way to tell her I don't see her as lover anymore?

pls no hate comments

I don't have feelings for my girlfriend of 5 years, what should I do?
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