1. "It helps remind me those memories I shared with you."

2. "It helps me remind those memories I shared with you. "

What are the mistakes in second one and how is these two sentence different despite having the same meaning?

Question

1. "It helps remind me those memories I shared with you."

2. "It helps me remind those memories I shared with you. "
 
What are the mistakes in second one and how is these two sentence different despite having the same meaning?

Answer

Should be:

1. "It helps remind me of those memories I share(d) with you."

2. "It helps me remember those memories I share(d) with you. "

I think "share" can be in the present tense, as you still share those memories, presumably...

Answer

Though the meaning is not 100%, there are issues with both sentences:

1) Prepositions is missing - It helps remind me OF those memories i shared with you. 
2) Remind is a transitive verb (needs an object) - It helps me remind YOU OF those memories I shared with you

Answer

Yes Joe is right. But maybe for the second one you mean "It helps me REMEMBER those memories I shared with you"