Tell them, "My grief journey is mine. It's for me to navigate through. My new relationship has been an added blessing in my life after a great loss." Then don't say anything else. If they continue coming at you in a negative way about you dating again. Tell them, "I will no longer engage in this conversation. Have a nice day." and walk away. This will send a clear message, you are an adult, it's your grief, your life, your decisions, and none of their business. Hope this helps. God bless you. Prayers & Hugs