Something that trails behind or follows something else can represent:
One event that happens (or happened) after another in your life
The idea of being "pulled along" or supported financially, emotionally, mentally, etc.
The idea of following rather than leading, copying someone, tagging along, or "riding their coattails"
The idea of following (a leader, a trend, etc.) blindly or without thinking for yourself
An add-on or accessory, something that is an afterthought or not essential
Your issues or emotional baggage that you "carry with you" wherever you go