I own Belleza Venus and i know how frustrating this issue is as i found myself many times like the OP teleporting to different destinations and my mesh body had completely vanished. It's true you can not see this happening to to yourself, only others can see it. My little trick was to wear my Belleza hud always and everytime i teleported anywhere i would try to remove an alpha strip out of my knee or some other region on my body. If i could not see the strip was removed i knew i had this issue and a relog was the only way to get back to normal.
After almost pulling my hair out many times with this problem i decided to try different things to see if i could address this and maybe find a solution and tried attaching the Venus to my hip instead. It's attached by default to the hand when you receive it from purchase. To my relief i found this fixed this issue completely. I tested it that day and hopped around to over 20 plus sims one after the other and when i finally stopped and tried the ultimate test and try remove that alpha strip on my knee, i was so happy when i seen it worked. That would not have happened when the Venus was attached to my hand, not a chance! So this issue definitely seems to be something to do with the mesh body being attached to the hand by default.
I have not experienced this issue once since i changed the attachment point to my hip and i done this at least 3 months ago! It is so wonderful to not to have to relog anymore just so i can get my mesh body back so everyone can see it again.
So Rhonda is right in her suggestion to try change the attachment point to some place else and see if it works for you. I can't guarantee this will work for everyone but it's certainly worth trying.