I assume by no start you are talking the motor. When you are plugged into shore power, you have a converter/charger that converts the 120v to 12v for the coach and also charges the coach batteries.
Your Seabreeze is like my Dolphin. That onboard converter/charger is not connected to the chassis 12v system nor does it keep the chassis battery charged. My chassis battery would go dead in a week, connected to shore or not.
On the other hand, when the motor is running, it does charge the coach batteries. This is to keep them charged between campgrounds.
You may have a "Start / Boost" switch on the dash. What that does it temporarily connects the coach batteries to the chassis battery to start the motor if the chassis battery gets run down. This is handy to have but, it still doesn't eliminate a big problem. Because a "starting" battery will soon be worthless if it discharges too many times or is left very long in a discharged state.
Mfgs eventually put in "BIRD" systems, which creates a bi-directional charging system. So when on shore, the chassis battery gets charged too. If you don't do something soon, you will be replacing the chassis battery often.
As previously mentioned, a Trik-L-Start is a cheap and effective way to eliminate this problem and basically gives you a BIRD system. I did this a few years ago and works perfect....install and forget it and a no-brainer to install.
An option would be disconnect the chassis battery when parked. To make this easier, you could install a manual disconnect switch. However, you still want to fully charge it once a month.
Also, if you have other questions regarding your National Seabreeze, post them in the National RV Owners forum.