All of us come to this way of eating with varied backgrounds, fears and experiences.
One always has to take past medical conditions into account, as well as particular pre-existing conditions.
It does not sound like you have any of these, but you do have fears.
First, to alleviate the fear about eating meat: You are not being advised to gorge on meat. Dr. D'Adamo makes several recommendations in the book concerning which meats to eat, how much of them to eat and how often.
Second, it is not required to eat meat. You might start on the diet by starting to avoid the Type O avoids, such as wheat, corn, vanilla, etc, etc. You may then choose to add meats such as beef and lamb if you want. It's a recommendation, not a requirement.
Go slow, treat yourself right, and learn to let go of the fear, which was implanted by inappropriate, but well meaning mis-education (how's that for a tongue twister :-)
PS: I'm not ashamed of my name or stating who I am. We are a community here in this 'cyber village.' Supporting each other as we learn and become healthier.