I've had to deal with a violent stalker. So I would advise that, providing you have the ability to do so, one should look into their state laws on Concealed and Open carry laws. I have had open carry end confrontations immediately. They get close enough to see the holster and it ends. Most thought I was a LEO and as long as I did not ID myself as such, it was okay.
Firearms at home. Everyone in the home needs to have firearm safety taught to them. Love them or hate them but the NRA's eddie eagle program is superb for the young ones (no, I am not a member). Or do what my father did and tell me from when I was about four that the firearms are never to be touched without him there. He also took me out shooting with him when I was older. I have mad respect for ANY type of firearm. If you have multiple firearms, please keep them in a safe and place whatever trigger/chamber guards that you wish. For a small price you can also have a pressure pad added to the home alarm system (most firearms used in crimes by felony criminals are stolen). I live alone but the only firearm I keep loaded is my sidearm, which is never any more than a few feet away from me.
Training, training, training. Whomever you select for your firearms training should also be able to teach you the local laws and run you through several shoot?/don't shoot? scenarios. If you use your firearm and are taken to a grand jury hearing, you can expect to spend as much as $10K in legal expenses. If you radically change the type of carry weapon, make sure to also go and get training with that, just in case you are called to court. The company I received my training from has a written policy of testifying for any student that graduates from their courses and they keep track of make, model, and caliber that you train with.
If you cannot pull the trigger to stop someone from hurting you or a loved one then do not have a weapon in the house. However, keep in mind that hot robberies (homes that are broken into while the owners are home) only make up about 13% of all reported home robberies but also makeup up to 60% of reported rapes. Criminals do not want to be caught, as a rule, so if they come in while you are home then chances are they plan to do unpleasant things to you and your family.
Avoid confrontations the best that you can. Take some practical martial arts training that focuses on self defense and not the tournament floor. I have studied in kenpo, jujitsu, and wing chun kung fu and all are excellent choices for close encounters. If you are carrying a firearm DO NOT engage in hand to hand combat. That allows the person to get close enough to grab your weapon.
If your state allows for it, carry a good can of mace. Not pepper spray! I carried OC-10 with me and that was always the first thing used. If they shrugged that off then the pistol was drawn. This will also help keep you out of court as it shows you were only trying to stop and not kill the attacker.
Always keep a cellphone on your person and when you go to sleep at night. If you carry a weapon and have to use it then you want to be the first to report it.
Lastly, only use a firearm if your life or the life of someone else is in immediate danger. The criminal must have the means to inflict greivous bodily harm in order for your shooting to be considered self defense. If the criminal runs, do not pursue but call the police and file a report.