my oldest cat won't look at me

Velvet is a 5 year old cat (she was my first cat) and she won't look at me
in the eyes. When I pet her, she averts her gaze and keeps her head turned
away from me. She has only begun this a few months ago Does anyone have any
ideas what the problem may be? She has always been a loving cat but she
doesn't get into my lap anymore or sleep on the bed with me as she used to.

Does anyone have any ideas what is up? I have three other cats. Thanks,

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