Depth of field? I think that's the depth of field "distance" interfering with the UI and as a post-process overlay effect I don't think you can easily separate the UI elements although opening the .cfg file for the author of the effect you are using and looking for a "focus" setting and altering that might possibly help minimize the problem.
ReShade 3.0 allows for a in-game UI making this easier as you immediately see the effect from altering a configurable setting but not all shaders are 3.0 compatible yet and 3.0 itself is still in beta.