Buffy, if the breathing exercises help, by all means keep doing them. Also, although the phrase "in-laws" is an instant stressor for some people, that doesn't sound like it's the case for you. You say you get along well, so I think it's great that you have people there to help out; it always worries me to hear about a woman with a complicated pregnancy who's home alone. Maybe your in-laws can do more to help out. Tell them how concerned you are and ask them to take over your chores or start on the nursery. With that many people in the house, you shouldn't have to lift a finger! Don't feel the need to play hostess. They're family; let them pamper you. Also, see if you can you start your maternity leave early. Even sedentary work can be stressful; it's certainly more stressful than rest.
On the other hand, don't ignore the bp or hope it will go away. Stress reduction can help, but it's no substitute for careful monitoring and possibly meds. Follow up with your doctor as often as you need to.
DH Bill (39)
The Mightiest Little Angel