# Troubles that cannot be numbered surround me

"there are more troubles around me than I can count" or "more troubles come to me than I can count" 

# my iniquities

"the consequences of my iniquities" 

# have caught up with me

The writer's iniquities are spoken of as if they were his enemies who were harming him. 

# I am no longer able to see anything

This may mean that the speaker is crying so much that he cannot see anything because of his tears.

# my heart has failed me

"I am very discouraged"