There are several errors:
1) Lack of plural agreement between "Our" and "life".
2) Missing "so" before "heart touching"
Also, I would go with "heartfelt" as Peachey suggested and make some other punctuation and minor changes. I've used uppercase below only to emphasize what words have been changed:
Our LIVES ARE a combination of memorable days. Out of all days, some days are forgotten while OTHERS are SO special and HEARTFELT that we CANNOT forgot them and they remain fresh in our minds. Memories remain inside us forever and walk with us.