Yes if is impacting work, tell your manager so they can manage you appropriately, its litterally their job.
No detail is required here, just let them know there's something going on (a family issue, health issues, relationship issue, whatever vague-ry you're comfortable with) and let them know the impact you think is having on your work and how long you expect it to be for. Discuss any reasonable adjustments you'd like (less cust facing work, flexible deadlines, reduced case load, flexible hours) and for how long, and tell them when you'd like to discuss again (e.g 'I'll be in a position to discuss again in 2 weeks tone, should we put something in the diary to review my <reduced cases/flex hours/whatever it is> then)
If you don't need anything to change still voice that theres something going on, that you're aware your mood/attitude/ability might be impacted and while you don’t need any adjustments right now, you wanted them to be aware, perhaps mention you'd be happy to discuss again on x date if you think things are still being impacted.
That's it, no personal info or discussion needed, just enough for them to manage you and your work better.