There are a few problems with this.
1. Poker IS gambling. (unless you're playing only play money games)
2. People who have a knee-jerk opposition to what we do cannot be reasoned with.
3. Daddy will always find a reason to dislike his daughter's choice in men.
This all being said, you will encouter those who are not automatically opposed to earning a living playing poker, but are still not comfortable with how steady the income stream can be. To them, the best approach is to liken it to any other new business. Or liken it to being a floor trader on the NYSE. Or liken it to being a farmer (no matter how well your choose your crops, how hard you work, etc., the weather is a huge luck factor).
There is a risk factor in all careers. The more independent you are, the higher the risk (AND the higher the return).
If someone will listen to reason, be honest with them. Be clear that the 35% short term luck factor is WHY it is possible to earn a good living at poker. Explain that there are very few professional chess players because weak chess players not only can't beat good ones, they don't think they can often enough to want to bet on their own play.
But be aware that the kind who will listen to reason are in the minority and in most cases you either have to adopt the "who cares" attitude and take your lumps or devise a good cover story and stick with it.
And don't hide it from your girlfriend. That will bite you in the ass worse than anything.
If she likes your money and doesn't care where it comes from (or isn't smart enough to care), trust me, you're better off without her regardless of how great her body is and how much she rocks your world in bed. That'll all wear off after a couple of years anyway.
