Is sex a basic need ?

Do we as humans have a basic need for sex ?
I know we crave love and affection and if we are starved of both either as children or adults, it can effect us greatly.
But as adults do we NEED sex ?
Do men NEED sex more than women ? And indeed it is said that to be healthy a man should ejaculate frequently.
I ask this, as a bf I had (not quite an x) been seeing before I became ill with depression, ( and hence have not left my house, or more truthfully my bed ) told me something today that quite upset me.
He admitted that at the weekend he booked the services of an escort, but as the appointment time approached he cancelled it. He told me he couldn't go ahead inspite of being very sexually frustrated. It wasn't what he wanted.

I was devastated by his confession and wondered how he could consider having sex with an escort. He stated that 'he is a man, and I have needs, and that a w*nk in the shower is not enough'
He has not had sex, or seen anyone else in the time I've withdrawn, and not seen him. That has been a year now, and every week he does ask to see me, and I can never motivate myself to see him. My self esteem is very low and I feel I've put on weight, so I hide away.

We had a good sexual relationship as we both have high sex drives. I know he masturbates every day, sometimes twice.
I always hoped he'd be patient and wait for me to feel better, well enough to see him, and he's never stopped asking to see me.
He tells me often he's sexually frustrated and that he needs me sexually, and I always told him when I do see him, reunion sex is not on the menu !

His confession made me wonder, if it would have been so wrong had he had his hour of release.
What if When we do see each other if we have hungry, reunion sex ?
What about FWB ? Are they just fulfilling a need ? Or is it wrong ?
I too miss sex, but also the closeness of being with someone I care about ( love?)
I know masturbation 'scratchs the itch' as it were, but you can't beat good sex / lovemaking in its many forms.
I am so glad he changed his mind about the escort , even though he never said, it was because of me, and my feelings. He said It just was not what he wanted afterall.

Please tell me what you think.

Sorry for the long post.