It's a strong term but here's how I define it: a sexless relationship is one where there has been little to no sexual contact of any kind in the last 12 months plus - this isn't just about intercourse - it is about there being avoidance of all sexual touch and contact. Naturally, there are times in life where sexual frequency is reduced or rare (such as through illness, grief, trauma, employment difficulties and during pregnancy and after birth). But these are usually temporary and sex resumes in some way when healing has happened.
A sexless relationship is easily identified by long-term avoidance in the absence of the above temporary factors (or maybe one of the factors above has a sense of completion but sex hasn't resumed). Sex might not be possible because penetration is not possible (as in cases of sexual pain) or it could be that old negative experiences have re-emerged and it is difficult for you to move through them and be present in sex. Sometimes, cultural beliefs about femininity, womanhood and sexuality are creating a block to being sexual and sex is shrouded in guilt and shame. Sexless relationships are also commonplace amongst couples that have a lot of distance in their relationships - usually because of deployment with the ADF or being FIFO (fly in, fly out) in remote locations.
Regardless of the reason, I really enjoy helping women gently resume or start sexual touch and contact with their partners. Her comfort and her yes always comes first. It's really rewarding seeing her dissolve the blocks and start allowing herself to bud open and I'd love to help you too!