(CNN) In letters to the daughter of a former prison guard, James "Whitey" Bulger lamented his failing health but said he wanted to be alive when his girlfriend got out of prison, the Boston Globe reported Tuesday.

Bulger, leader of an Irish mob gang from South Boston and an FBI informant for many years, was killed in a federal prison in West Virginia last year hours after he was transferred from a facility in Florida. He was 89.

The Globe gained access to some of the letters Bulger sent to Candace Lind, whose father ran the prison laundry at another prison -- Alcatraz -- while Bulger was there in the 1950s and '60s. She began writing Bulger in 2014 after he had been sentenced to life in prison for 11 murders.

The paper reported that Bulger wrote that he had had eight heart attacks and had chest pains he eased with pills and oxygen. He said he wrote daily letters to girlfriend Catherine Greig and wanted her to come visit him after she is released in 2020, the Globe reported.

Bureau of Prison records obtained by CNN last year state that Bulger suffered from high-blood pressure, aortic stenosis and prostate and bladder problems. But prison authorities determined he had improved enough to be sent to a prison with fewer medical services, the Globe reported.

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