tikituki - if it helps, I had a friend on PS4 join my world and it looks perfectly fine to him. Looks like it's just a graphical issue, but I'd recommend backing up your worlds anyways!
Looks like we're all suffering the same issue. I put all of the info I've got here: https://bugs.mojang.com/browse/MCPE-109904?focusedCommentId=859020&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-859020
The menu works fully - I managed to get UI reader working and through that I was able to navigate the menu. By going into graphical settings and selecting "UI Profile" -> "Classic", it appears to reset the UI and you'll (hopefully) be able to see the menu again. Unfortunately graphical issues in the game make it practically unplayable until they fix the bug anyway.
I've put down all the info I have here: https://bugs.mojang.com/browse/MCPE-109904?focusedCommentId=859020&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-859020