She claims she receives death threats or implies she's going to kill herself as a reaction to the comments every time she tweets something tone-deaf, mistakenly offends the woke puritans or gets called out on a lie or cruel behaviour. She did it when people criticised her for her treatment of Caroline Flack - she implied she would follow her example. It's just her way of shutting down the conversation and making people back off, thus allowing her to continue behaving the way she does unchallenged. This is because she's a narcissist who doesn't feel she needs to engage with either justified pushback to her behaviour, or even with the crazy wokier-than-though fake moralists of whom she aspires to be queen, when they decide she's broken one of their increasingly-convoluted and draconian commandments.
People can't 'send' her death threats anyway because she doesn't have open DMs anywhere; it's just another low lie, just like her implied suicide threats. She's posted and quickly deleted a couple of very dramatic and exaggerated fake threats before though. She relies on the fact that people naively assume no one would be so low as to fake receiving death threats or fake suicidal ideation. This insightful article was originally titled 'Jameela Jamil and the weaponisation of suicide' before madam made a fuss about lawyers:
Too many celebs and campaigners are using suicide to try to win the argument.
www.spiked-online.com
As others have said, there is a degree of satisfaction in seeing someone who behaves so perniciously while affecting the most vacuous kind of moral righteousness ultimately be hoist by their own petard.