To have the odds/cards stacked against you - to be very unlikely to succeed because you are not in a good position. Example - "I know the odds are stacked against me, but I wish to run in the race anyway.
To rub salt into the wound - to make a difficult situation even worse for someone. Example - "When Sheila found out she had failed the test, she was upset. The professor rubbed salt into the wound when he told her that she would not be able to graduate because of her poor mark"
To take something in your stride - to calmly deal with something that is unpleasant and not let it affect what you are doing. Example - "There are often problems at work but she seems to take it all in her stride"