I have two previous answers about female inheritance that you might want to look at - here and here - that can be seen as important background reading to understanding inheritance. Following on from them, you can see that very little is set in stone among the upper and gentry classes: it largely depends on whether there was or was not a settlement, and what was in it.

By 1887, Married Women's Property Acts had been passed that allowed a woman to be considered a separate person in law, and legally retain what she owned before the marriage or inherited after it. However, in practice, many women still gave such things to their husbands, and one who married young would still typically have a dowry that went from her father to her husband. So if she came into the marriage actually owning wealth that continued to stay in her name (and the marriage took place just a few years prior to 1887, because the Acts weren't retroactive), yes, she would be entitled to that; if she came in as a rich bride and the money became her husband's, it was his to dispose of. He could leave it all to her, but if they had a son, it would be somewhat looked down upon not to leave it to him as the new head of the family. If they had no heirs, there was no general legal requirement for what should be done with the money in a will, but there might have been a settlement that required some or all of it to go to the widow.

As for titles, yes, she would keep it. She would be called the Dowager [whatever her title had previously been] if the heir to her husband's title was her son or grandson, and if not, she would be addressed as previously.