How to talk to my partner about my self harm and suicidal thoughts?

How do I discuss my struggles with self harm and suicidal thoughts/attempts with my partner? I’ve been doing nothing but hiding it from everyone close to me because it’s such a taboo and hard to discuss topic and I never want to come across as overly “edgy” or be one of those guilt tripping people who use their negative thoughts of this nature as a crutch for their negative actions. I need advice on how to gently explain my situation, and explain how difficult things are and how much this is truly affecting me without using unhealthy or overly concerning terminology.