A crash can symbolize stress in your life. An airplane crash signifies a difficult birth – your arrival on the planet did not go as smoothly as expected. The event was traumatic due to either a brush with death or a negative emotional experience.
If you lost a child due to miscarriage or shortly after birth you can also dream of airplane crashes. For example, a woman whose baby died shortly after being born dreamed she witnessed a plane coming in to land flying too low. It passed just over her head and crashed behind her. The force of the gust from the blast knocked her over.
A small / baby car crashing into a bus can indicate you were an unwanted baby. In this case the bus symbolizes feeding at your mother’s bosom (bust) and picking up on her feelings about your arrival.
To dream of your partner dying in a car crash is indicative of a relationship which feels like the one you do not want to lose. It is a common dream for people who have had a previous difficult relationship. It does not foretell the death of your partner. Rather it shows your fear of losing them. The dream is showing you this fear only because it is affecting your relationship in someway. Do not put pressure on yourself or your partner because you think something will cause them to leave. Enjoy what you have now.