The Anxiety Community - Avoidant Personality Disorder vs. Generalized Social Anxiety Disorder
They're very similar, avpd is like a more severe version. I believe there's a couple of threads that ask the same question of mapping out the difference. I'll link you if I can find them.
A lot of AvPD things sum me up perfectly on there, particularly
"Severe social inhibition and feeling of social inadequacy and inferiority"
This was a big part of the reason I cut contact with my high school friends, as they went to uni and had an amazing time, making loads of friends, going to parties and getting partners, while I was having a horrible time of avoidance, never really made any proper friends and my experience has basically been the exact opposite, so I couldn't bare to see them anymore and hear how inferior my life has become compared to them, so cut contact.
"is preoccupied with being criticized or rejected in social situations"
This is a big one for me, as the problem was when I moved into a student house, I was getting the very ridicule and criticisms that I feared constantly, so I then ended up literally avoiding all contact with the people in my house.
"Appear self-involved and uncaring, but long for affection and fantasize about idealized relationships"
My whole life now I haven't got any friends to talk to is spent fantasizing about an ideal relationship, whether it be romantic or just a close supportive friendship that I've never really had, but the more I avoid social situations, the less likely my fantasies are to come true.