Or just get attack dogs, of course those dogs may be more likely to attack your a loved one than you are likely to get attacked. Heck all the money I've spent in martial arts I could easily take back and spend on home security.Here we get into a fundamental fact of human psychology: people are bad at evaluating risk.
Terrorist attacks, mass shootings, and home invasions by armed gangs make the news because they are scary and unusual. Statistically speaking, however, you are more likely to be killed by lightning than by a terrorist. If you are spending thousands of hours of hard training because you are afraid of a highly unlikely event that you will a) probably never encounter in your life and b) would have only a small chance of successfully handling with your martial arts training, then that is a poor allocation of your available resources.
If you are that determined to protect yourself and your family, you are better off devoting that time and energy and money towards the factors that are actually likely to kill you, i.e.:
Improve your diet and exercise: Heart disease and diabetes kill more people than 2000 times as many people each year in the U.S. as terrorists, mass shootings, and home invasions put together.
Take a defensive driving course: tens of thousands of people die from traffic accidents in the U.S. every year.
Take care of your mental health: suicide is the 10th most common cause of death in the U.S.
Teach your kids how to swim.
Heck - take the time to fix that loose step on the back steps. It's more likely to kill you than terrorists or a home invading gang.