my son has been arrested 5 times in the last few yrs. he has an undiagnosed mental problem that is getting worse. this time is for strangling his gf. bond denied. is this serious prison time?

Yes - this could get ugly. Domestic violence with quite possibly an attempted murder charge added on, is probably why the bond was denied. The courts are having no problem handing out long, severe punishment for crimes against women - and rightfully so. The girl that was strangled is a weaker victim, your son being arrested five times is not going to look good to the judge making the decision on sentencing.