These things are sent to try us.
This expression is commonly used when things go wrong.  Anything which tries our patience, like the irritation of bootlaces which do not stay fastened, or serious problems may cause someone to say it.

A tight corner is a metaphor for a difficult situation.  It can be difficult to extricate oneself from this.

Fraught with problems (or difficulties) is rather an old-fashioned expression. 

I’m fraught.  A person can be fraught too.  Stressed out is used more now.

That’s hard to take means difficult to accept.  A longer similar expression is a hard pill to swallow.

It casts a shadow may describe some trouble, which is always at the back of someone’s mind.

A rough passage is another metaphor, this time from sea-crossings.  It usually refers to an illness someone has suffered.

Someone who has been through the mill has seen troubles in life.  Hopefully they have not been completely ground down by them.  A mill grinds grain into flour, for example.

A fly in the ointment is one bad thing which stops a situation from being perfect.  There is a book by Anne Fine with the title Fly in the OintmentShe writes for adults as well as for children.  This is one of her grown-up books.  I have read and enjoyed a good number of her books.

In the throes of is often associated with a painful experience, but may be applied to being in the middle of a big job.  Two examples: ‘She was in the throes of labour.’  ‘I am in the throes of spring-cleaning.

Hampered by means encumbered or hindered.  A picnic hamper is a large basket.  It would be possible to be hampered by a hamper!

You’ll come to grief is a warning that you are putting yourself in danger, possibly emotionally.

A well-known passage in the Old Testament predicts the sufferings of the Messiah.  Isaiah 53.