If you are having some sort of difficulty at home that is serious, it is sometimes extremely hard to not bring these kinds of things to work with you. When the problems get bad enough, you more than likely find it extremely difficult for you to maintain your focus on the job. However; it is probably not the wisest thing to do, bringing those problems with you to work.
It can be a pretty sticky business if your personal issues were to get spread around the office and sometimes you might find yourself in hot water or even out there with other job seekers looking for work if your problems get too out of control. There are ways though that you can manage your problems and not let them become the office gossip.
Instead of letting the problems you are having at home dictate how you are going to behave and perform, instead you should try using your work as a place that you can actually get away from the problems at home that might be haunting you. You can use these work hours to just focus on your work and this will give your mind the needed rest that it needs from whatever is going on in your home life. This is one reason why a lot of people get lost in their work, to try and alleviate the pain they are suffering at home.
It's important that you do your best to make sure that all of your personal problems are kept to yourself and do your best to keep other employees out of it. It really is none of their concern and you need to try and keep it that way. There really is no reason why everyone you work with needs to know what's going on at home. By making sure that you keep your home life completely separate from your work matters is not going to hurt your work. Letting the who place know about it, could even jeopardize your job.
If things are getting too bad for you to be able to separate work from home it might be in your best interest to try and schedule a one on one meeting with your boss. Do this only if you believe that the problems from home are beginning to affect your job performance. This might help alleviate any concerns he may be having about your recent change in behavior.
When you sit down with your boss, there is no need to go into any lengthy details about what the problem is that you are having at home, just stress that you are going through a very hard and private issue at home and that your really don't want to burden him with all of the details.
If you feel that you need some time off, you should ask if you can take some of your vacation time, or sick time and if you don't have any of that available then see if you can't get some personal time off so that you can have some time to deal with the issues. Hopefully you will be able to use that time to take care of your problems and come back to work feeling better and more refreshed.
Whatever you do, never feel bad about any time that you do ask to take. You boss should be able to understand that you and he will both be better off because it should help you be more productive when you return to your job.