But you don't know that. Jesus never said that. Even if he did there would be no way for you to know whether it was true.Ironically, according to
Act 14:15-17 WEB 15 “Men, why are you doing these things? We also are men of like passions with you, and bring you good news, that you should turn from these vain things to the living God, who made the sky, the earth, the sea, and all that is in them; 16 who in the generations gone by allowed all the nations to walk in their own ways. 17 Yet he didn’t leave himself without witness, in that he did good and gave you rains from the sky and fruitful seasons, filling our hearts with food and gladness.”
He's given you a good life, so you can know that he is good and loves you.
But if you ignore his goodness and disregard his warnings, upon your death, the loss of all your life and family will be your own doing.
An eternity with Jesus is the continuation of life, but way better. An eternity separated from him means the end of all his goodness and life.