Our B190 felt this way sometimes. Most trips everything worked perfectly; others, random things would fail. I know it's frustrating to have problems with your camper seemingly every trip. You get into the mindset of, "What's going to happen next?"
There are a couple possibilities:
1. You need to use it more, so that the trips where you have problems are a minority, or
2. You've fallen out of love with this one and it's time to move on.
The B190 wasn't a problem child; other than a few minor recurring issues it usually worked very well. But getting the new camper (a '95 30' trailer) last summer rekindled our love of camping. We've camped more this year than any other two years combined. It's more fun than ever! And, most trips go by without me having to open the tool box - there are some issues now and then, but they're infrequent enough that in a strange way I sort of enjoy the distraction.
1995 Airstream Classic 30' Excella 1000
2014 Ram 2500 Crew Cab with Cummins 6.7L Diesel
Sold but not forgotten: 1991 Airstream B190
Sold: 2006 F-250 6.0L Powerstroke Supercab