Crashing shortly after entering Realm server

My game crashes shortly after entering a Realms server. I've played on this server before, but since 1.8 I haven't been able to log on. I then tried updating Java to no effect.

What I expected to happen was...:
I expected to log on to the Realms server and play as per usual.

What actually happened was...:
The Realms server opens up, it lags for a bit and then freezes shortly before crashing completely, opening the launcher anew and presenting me with an error report - the most recent such reports are attached.

Steps to Reproduce:
1. Open Minecraft Launcher on an XP machine
2. Launch Minecraft
3. Join Realms server
4. ????
5. Crash