As you get older, you lose a lot of memories, but the ones that have strong feelings attached to them last until the end.
この場合、次のような言い方ができますよ。
ーAs you get older, you lose a lot of memories, but the ones that have strong feelings attached to them last until the end.
「歳を取るにつれ多くの記憶を失うが、強い感情を伴う記憶は最後まで残る」
memories that have strong feelings attached で「強い感情を伴った記憶」
to last until the end で「最後まで残る」
ご参考まで!