Trouble orgasming. 😞

I've never been the woman who orgasms easily or quickly or every time. Although lately it seems to have gotten way worse. Often times I even get almost to the peak and then it just doesn't go through all the way. My relationship with my husband is amazing though, we are great in every category. I don't know why this is happening or how to fix it. This is really affecting my desire to have sex. I feel like a failure and I feel disappointed and frustrated. My husband is wonderful and goes to great lengths to try and help me cum. Also I can only cum via cliteral stimulation, I've never cum from straight up penetration. If anyone has suggestions I'm willing to hear them or if you can relate then let me know I'm not alone. Thanks in advance.