The sad reality is that sometimes relationships end when you don’t want them to. I am so sorry this has happened to you, 5 years is a long time with someone. Please be gentle with yourself, if possible, get in touch with a therapist or at the very least, surround yourself with people who love and care for you. You will get through this

Distance yourself as much as possible, giving uninterested responses, dry conversation. When they ask what’s wrong, express that you’ve gotten very busy and you’re tired. I have successfully done this with friends that I never thought I could do this to. Trust the process