I have never been able to reach ejaculation with a partner

ANSWER

This is relatively uncommon, but certainly there are many other men experiencing a similar situation. Typically, it is a problem with men who have relied primarily on masturbation to reach an ejaculatory climax, and particularly if they become dependent or even addicted to watching porn as the primary way they become aroused. If this is your situation, you may try to gradually wean yourself away from masturbating while watching porn, and save your arousal and juice for when you are with a partner.

Another point worth mentioning, is that there certainly is no requirement to come to an ejaculation. In fact most forms of sacred sexuality practice, including both Tantric and Taoist, place emphasis on delaying the ejaculation, including sometimes for weeks or even months at a time. Note, this does not mean you don’t have orgasms, but rather that you learn to work with the sexual energy to separate orgasm from ejaculation, so you can have orgasms without ejaculation, and can also have multiple orgasms. Most men (but certainly not all)  find the experience of orgasm without ejaculation, to be far superior to a simple ejaculation.