Debian freezes after some time

when I open my laptop after some time of it being closed, it will work for a few seconds, then slow down considerably for about 3 seconds, then completely freeze, to the point that even REISUB won't work, it also happened once when I was using it for a few hours, I don't think it's because of heat, since it happens right out of being suspended. any ideas as to what it could be?

I'd start with firing up htop and see if any services are acting weird

It's odd that magic sysrq doesn't work given that always works provided the kernel is still functioning. Does syslog show anything?

I'd check RAM. One bad stick of RAM I had caused random intermittent freezes, similar to this just not right of out of sleep or suspend because this was a desktop.

is everything in the kernel loading correctly after the suspend? Linux I believe if the kernel module does die clean when suspending the kernel kills the module and then doesn't load it again on reload. I know i seen modified code that will reload the module if the module state doesn't matter but that is rarely the case.

left htop running, and at the time of crash "/usr/lib/rtkit/rtkit-daemon" was getting 160% of my cpu. would you happen to know of any way to disable it?

did a fix I found here, now that exact process doesn't take many resources, but the problem persists, and now all processes seem normal(under 1% cpu usage).

Try changing to another tty and see if it freezes there, might be X or graphics driver related.
You can also try running a live environment for a while and if that freezes it's a hardware issue.

I would start a new session if you haven't already.