It is important to help him by not raising his expectations regaqarding finances.
Rather than look at the negative aspects of the marriage look at the enduring good things -children etc...what a legacy.
After a 30 year marriage it can't have been all bad.
Remember the issue of contribution ie who did what and brought £ into the marriage or in the marriage will dull and not really matter.
In capital terms the starting point will be an equal division. She helped bring up the children whilst his career improved so approaching finances in later life is not so difficult.
In later life ofter one approach is to divide capital equally, attain a pension share
which is fair often after an actuary's report as to value with a view to pension sharing
(or a pension's offset
that is the other party getting more capital) and then spoause maintenance for a time or until pensions kick in.
In fact, the relevant principles are set out in Section 25 of the Matrimonial Causes Act 1973 :
25 Matters to which court is to have regard in deciding how to exercise its powers under ss. 23, 24 and 24A
(1)It shall be the duty of the court in deciding whether to exercise its powers under section 23, 24 , 24A or 24B] above and, if so, in what manner, to have regard to all the circumstances of the case, first consideration being given to the welfare while a minor of any child of the family who has not attained the age of eighteen.
(2)As regards the exercise of the powers of the court under section 23(1)(a), (b) or (c), 24 24A or 24B]above in relation to a party to the marriage, the court shall in particular have regard to the following matters—
(a)the income, earning capacity, property and other financial resources which each of the parties to the marriage has or is likely to have in the foreseeable future, including in the case of earning capacity any increase in that capacity which it would in the opinion of the court be reasonable to expect a party to the marriage to take steps to acquire;
(b)the financial needs, obligations and responsibilities which each of the parties to the marriage has or is likely to have in the foreseeable future;
(c)the standard of living enjoyed by the family before the breakdown of the marriage;
(d)the age of each party to the marriage and the duration of the marriage;
(e)any physical or mental disability of either of the parties to the marriage;
(f)the contributions which each of the parties has made or is likely in the foreseeable future to make to the welfare of the family, including any contribution by looking after the home or caring for the family;
(g)the conduct of each of the parties, if that conduct is such that it would in the opinion of the court be inequitable to disregard it;
(h)in the case of proceedings for divorce or nullity of marriage, the value to each of the parties to the marriage of any benefit . . which, by reason of the dissolution or annulment of the marriage, that party will lose the chance of acquiring.
(3)As regards the exercise of the powers of the court under section 23(1)(d), (e) or (f), (2) or (4), 24 or 24A above in relation to a child of the family, the court shall in particular have regard to the following matters—
(a)the financial needs of the child;
(b)the income, earning capacity (if any), property and other financial resources of the child;
(c)any physical or mental disability of the child;
(d)the manner in which he was being and in which the parties to the marriage expected him to be educated or trained;
(e)the considerations mentioned in relation to the parties to the marriage in paragraphs (a), (b), (c) and (e) of subsection (2) above.
(4)As regards the exercise of the powers of the court under section 23(1)(d), (e) or (f), (2) or (4), 24 or 24A above against a party to a marriage in favour of a child of the family who is not the child of that party, the court shall also have regard—
(a)to whether that party assumed any responsibility for the child’s maintenance, and, if so, to the extent to which, and the basis upon which, that party assumed such responsibility and to the length of time for which that party discharged such responsibility;
(b)to whether in assuming and discharging such responsibility that party did so knowing that the child was not his or her own;
(c)to the liability of any other person to maintain the child.]
The key here to your friend's depression is to get a "reality" check -sort out divorce and finances fairly and move on...don't reflect on the marriage breakdown for too long...it is potentially destructive...achieves little.
Probably not a post you were expecting but as many here will vouch for there is "life" after divorce.
Best of luck