Scott Mitchell, 57, said a specialist warned staying at home may no longer be sustainable for the EastEnders and Carry On star.
Dame Barbara was diagnosed with Alzheimer’s in 2014 and Mitchell has been campaigning to raise awareness of the disease.
He reportedly told a TV documentary made by the actress’ former co-star and on-screen son Ross Kemp that his wife moving to a care home is “the thing I’ve always feared”.
He said: “He’s (the specialist) basically telling me I need to prepare myself that at some point it may not be sustainable to give her the kind of care she needs at the house.
“I’ve had some fairly dark moments since he said that because there’s a part of me that knows that most likely is the truth and that’s what needs to happen.”
Mitchell, who according to the Sun newspaper will appear on Ross Kemp: Living with Dementia, added: “There’s another part of me which can’t imagine letting her go.
“I can’t imagine leaving that lady when she talks to me the way she does and putting her somewhere and her thinking, ‘Why has he done this to me?’”
Mr Mitchell and Dame Barbara tied the knot in 2000.