You can contest the contents of your husband’s will on the grounds that it does not make ‘reasonable financial provision’ for you, provided you have not remarried. You must claim through the courts within six months of probate being granted.
Your husband’s executors, his children by his former marriage and any other beneficiaries might oppose your claim. His children may also be entitled to claim for reasonable financial provision. In deciding your claim the court will look at what you might have been awarded if you had divorced your husband.