Should I take a break?

It will be 4 years in November, it’s been a horrible journey. I keep hitting a brick wall with everything I try, nothing works. Unexplained infertility. I’m mentally exhausted. I want to just have a break from trying, But I know if we do, we won’t have sex when it’s important so that “oh it happened when we stopped trying” phrase likely won’t be the case for me. On top of that I’m 38 this year so I don’t feel like time is on my side. And there’s a part of me that is worried that I’ll be delaying it happening if I give it a break. Any advice ? I’m very sad. On my second Letrozole cycle and my husband had a death in the family when I was ovulating so I only got to self inseminate once - only to find out self insemination isn’t very effective. So absolutely wasted cycle.