This sounds like a mental block to me. This link is to an older post here at medhelp where a PhD specialist talks about this kind of anxiety related to erections. Even though the stories (yours and the OP on the other thread) are different, the things that the doctor says is very helpful and may really resonate with you. Give it a read and tell me what you think. https://
www.medhelp.org/posts/Erectile-Dysfunction/Cant-beat-the-mental-barrier-and-maintain-erection/show/1024174
I agree with GR - sounds more psychological than physical. I don't know this for sure, but even if it turns out you do have a variocele, I don't think that would interfere with your sexual functioning. I would not necessarily characterize masturbation 3x daily as 'excessive', but you might not be doing yourself any favors with that. I think what can happen is that sex (solo or otherwise) could become a little routine, boring, etc., and you're not giving yourself time to build up the desire & urge for sex, so that could be contributing to your problem. I firmly believe that your erection problems are NOT actually ED - if you were really suffering true ED, you probably wouldn't be getting strong erections as you describe, so I think the variability is more related to your frame of mind at the time. I think you need to relax a little, put less pressure on yourself to 'perform' (TERRIBLE term, by the way...) and that will probably go a long way to getting past this. The link to the earlier post GR provided should help...