I think you should look at the niches you are in or your girlfriend's to start with. Also, it is not because someone is already adressing a specific issue that

I think you should look at the niches you are in or your girlfriend's to start with. Also, it is not because someone is already adressing a specific issue that someone else can't jump in with another solution (unless that competitor already has reached 100% of the market and even then your job would be to convince their customers that your product is better). You may have dismissed a few of the niches that you are a part of simply because of the "someone has already done it" stigma. If you are after a lifestyle business, stop thinking like you are building a startup.