People are allergic to proteins in the plants that get distributed through the air. They are not allergic to the smell of the plants. Your friend isn't allergic to the smell of tree nuts. She's allergic to proteins in the tree nut dust. The molecules that make up scents are too small to carry proteins. Marijuana allergies are real, but unless you're trapped in a room with someone smoking, you eat it, or you rub the flower all over your skin, you're not going to trigger that allergy.

Smoke irritating your lungs when you have asthma isn't an allergy. Smoke is an irritant, not an allergen. And sitting next to a campfire is exposing yourself to several magnitudes higher concentration of smoke than walking through an area where someone smoked some weed.

It sounds like you have really poorly controlled asthma and you need to be on better maintenance inhalers. The hives is likely you having a panic attack worrying about your asthma and being triggered by the scent of weed.

You need a therapist and a pulmonologist.

You're not going to outrun the smell of weed in any major city in a country that is on track to full legalization.