Unfortunately, A and E will be full of some genuinely sick people, several drunk people, some people with simple or what we call ‘uncomplicated’ toothache and several people who should have gone to their pharmacy or GP. If you do get to see someone from psych, you will be sent home. (Source: 26 years experience with mental health.)
OP, Psych Liason will look at several factors such as intention/plans, any recent attempts or self harm, and the support he has at home. Since your DH has you, and a warm, loving home and is not harming himself and not intending to, Psych Liason in my experience is likely to deem it much healthier for him to go home than to be admitted to hospital, which is really very traumatising indeed.
I would take him to the GP as an emergency appointment on Monday. The GP may prescribe medication. Ask what help is available in the community but also be prepared to ask for a referral to a private psychiatrist. You can get an ‘open referral’ so you don’t have to take a name into the appointment.
Of course you’re going to worry and that’s only natural, but in my long experience there is a significant difference between not wanting to go on and actually attempting to take one’s life.
wishing you all the best xxxxx