try TGA subcool's jilly bean. that's a happy deep relaxing strain
if someone is already anxious, sativas are a bad idea. potent ones are a challenge to anyone once you get too much in your system in that one woofing big hit too. i would suggest DNA's lemon skunk if you'd like to try something with a light high that isn't sensory or mandala's 8 miles high for a nice euphoric energy neutral high for anyone looking for a light sativa, but there are plenty of mellower to deep relaxing mids out there that are better suited to your needs.
anti-anxiety is a good keyword search term for you and euphoria should counter that at least some of the time. bubblegum, blueberry & skunk #1 would be decent classic strains for you to at least try for a stonier euphoric buzz. i'm sure there are many threads about anti-anxiety strains out there if you google a little. it would probably even have it's own sub-topic in a med use specific forum, and i think there are med use threads here too.