(2-part post):
You've not stated what sentences were imposed for the offences committed by your husband. They're relevant because they determine the 'rehabilitation period' after which, for most purposes, the convictions are regarded as 'spent'.
However, it's likely that non-custodial sentences were imposed, in which case it's likely that the rehabilitation period for each offence is 5 years. So your husband's convictions are already 'spent' (or will very shortly become so).
http://www.lawontheweb.co.uk/rehabact.htm
Once a conviction is spent, there is no requirement to declare it when applying for such things as insurance and for most types of employment. (Even if a question is worded as "Have you ever been convicted of a criminal offence?", the answer 'No' may be given, without risk of prosecution for deception).
However, some types of employment are exempt from the provisions of the Rehabilitation of Offenders Act. These are mainly jobs involved with the administration of justice, medical care or those involving close contact with children or vulnerable adults (which would seem to include people with psychological disorders) . When applying for these types of employment, convictions are never regarded as spent and must always be declared. However, declaring a criminal conviction does not normally automatically bar an applicant from employment; it's up to the employer to decide whether or not it has any relevance. (i.e. your husband isn't definitely barred from resuming his former employment but it's likely that most employers would be unprepared to 'take the risk').