I am not sure that a solicitor can be of much help at this stage unless you can show him a copy of the will.
You and your husband need to have a frank conversation, which you should have done when you were about to marry. If you can clarify the situation, then I would try to persuade your husband to accompany you to see a solicitor, complete with will, so s/he can explain the implications of it and what your rights as a widow would be - and vice versa.
Do you have children? You obviously have a chunk of savings as you offered to buy half his house when you married. If you die first, who will inherit your savings? Have you made a will?Without a will, it will be your husband, for the most part. If you have used a fair amount of your money on the house, there will be less for your children to inherit. Maybe your husband could consider that, and leave some of his savings to you.
My husband and I are on our second marriage, each with adult children, but we own our house as tenants in common, with a life interest so that the surviving spouse can stay in the house. I can see that in some situations this can create problems if the children are keen to get their inheritance.
As I said, before rushing off to see a solicitor yourself, you and your husband need to sort out the position.