Our garden is in the territory of a pair of blackbirds and we do provide them with some food to the extent that the male will sit on a chair outside the back door and look at us through the window, in a subtle way.
What usually happens, and this is confusing me, is that when I put food down for him the female almost immediately land and aggressively chases him away. She is so determined to do this that she'll often not have any of the food herself. I've seen her running around the garden after him and she is holding some of the food in her beak.
This is usual at this time of year. There is also a good chance it isn’t a pair. UK hosts a lot of migrant blackbirds, and younger birds also won’t necessarily hold a territory now.