Sabohan,
How much of a phobia is it? There are roaches, and then there are roaches. Woodies are very different from the pest cockroaches. They don't look like they're staring at you for a start. I actually find them interesting to watch, especially when they're moulting. The females retain the egg case until the young emerge, and a few weeks ago I saw this happening for the first time.
Okay, I'm studying zoology, so maybe I'm a bit different, but I admit that the idea of keeping a woodie colony gave me the creeps to begin with. Now that I've had one for a few months, I can put my hand in the tub and scoop out a handful of the little suckers without flinching.
I know it's difficult when you have a phobia, but I'd strongly encourage you to get used to the idea of insects before getting a beardie. I know very little about monitor diet and can't comment there, but I personally think that cutting insects out of a beardie's diet would be cutting out a healthy, natural source of nutrients, especially protein. Also, hard, crunchy food such as insects helps keep their teeth healthy. (I think I saw that on Shane Simpson's webinar earlier tonight.)