This is likely a hardware error. Bitcoin Core is very hardware intensive so it could be causing the crashes from working the hardware to hard. The only solution is to either upgrade your hardware or switch to use another wallet.
These crashes likely indicate that you have some faulty hardware.
it is 99% a hardware error, and from my past experiences, it has to do with the system somehow mismanaging power somewhere. based on what i know about bitcoin core, which takes up a fair bit of memory (ram) try running memtest (
http://www.memtest86.com/) for an hour or two, every test. if something comes up, its a memory issue and you should get those swapped out asap. if your system is stable without bitcoin core running, try getting hard disk sentinel (
http://www.hdsentinel.com/) on the off chance it might be a hd related issue. if it isnt either of those, its either a dying cpu or insufficient power supply. (cpu is unlikely, assuming your system is stable without core running. more likely, it might be the psu doesnt have the wattage to support your system with core running. however, its probably a memory error)
cant really suggest much else without knowing other pc specs / recent activity / changes though.