I think maybe you are overreacting to the fear. Have you ever tested? Have you seen her test results?
Neither of you are in a high risk age group, and if she has tested negative, then there isn't anything to worry about.
If you feel that you will never be able to to have sex again because of a fear of STDs, then yes, I'd say that you should talk to a counselor and perhaps your doctor about a referral to a psychiatrist for an evaluation.
STDs exist, of course, but most are curable, and the ones that aren't - like herpes - aren't nearly as bad as you seem to think they are. You're very concerned about getting genital herpes from oral sex, but if you have hsv1 orally, you are protected from that if you have hsv1 orally - you have antibodies for hsv1 that protect you.
Getting a blood test in Canada is difficult, but I'm told it can happen. Your doctor can do it, though you may have to pay for it. Just make sure it's a type specific IgG blood test. If you've ever had a cold sore, you have hsv1.
Globally, about 2/3 of adults have hsv1. You're going to have a hard time avoiding it, if you don't already have it.
When a fear of something interferes with your life, it's time to seek help for it. I hope you do. Phobias are real, and very treatable. I hope you find peace.