Had gastric bypass in 2005 and teeth keep breaking I now have 5 broken teeth and they even break on soft foods am taking vitamins regularly?

Ok. They can also be susceptible to the acid reflux which can occur from the gastric bypass. The acid destroys the enamel and makes it easier to get decay and erosion. Mi paste is good to use can reflux into the.
Maybe a conincidence. Gasttic bypass is unrelated to breaking teeth. I would not expect to see the two problems together unless there was some coincidental bulimea.... Often times teeth break secondary to a high caries rate. This can be hereditary or more likely it can relate to poor oral hygiene. It can also relate to a hereditary condition that results in malformation of the teeth like an enamel formation defect.
Vitamins won't help. Unfortunately, there are no vitamins I know of that can strengthen your teeth after they have erupted. If you had any conditions before your surgery, they could have come back to haunt you now. Many people who need gastric surgery have other problems like gerd and/or osa. Both of these conditions can have deleterious effects on your teeth that might not show up until later. Have you seen dds?
Calcium. It may be more difficult for your body to absorb calcium. It may be worthwhile to have your doctor check your calcium level and parathyroid hormone level as well.
Seek care. I can't see why gastric bypass surgery would affect the strength of your teeth. There must be other factors. Please seek professional care for an informed opinion.