First off, stop letting your friends and relatives make your decisions for you. And I'm not saying that to be offensive. The reason I'm saying that is, if someone hasn't already they will tell you, you can't do it. And if you let it, you will start believing it. And it's hogwash. Second, here's a link to a post I just finished that might help you find a niche or at least get an idea... https://my.wealthyaffiliate.com/keyword-niche-and-market-research/if-you-re-having-problems-finding-a-niche

Next, your idea of self improvement is a market I'm already in. you might get some idea's from it. If so, feel free to use them. Go to theinnerself.org I am VERY big into using ones own mind for self improvement, primarily because it works. There are several membership sites at clickbank you can promote. You can also go to youtube and search for Gregg Braden, Bob Proctor, The Secret, Law of Attraction and learn a good bit on the subject. I would give this self help area a lot of thought though. It's exceptionally difficult to promote, competition is high and there is a scarcity of material available to use to promote it.

I like what ( zshairulla ) just said ---The boot camp is a great start and will teach a lot ---then you will find what floats your boat --

Try going going through the affiliate bootcamp to get started and research the things you will love to promote. So you can start applying the training while going through the affiliate boot camp. Just a suggestion, all the best of success.

Work with something you love to do most... this way when you get overwhelm you'll have some leverage and motivation to continue:)

I would pick something you like, but make sure it's something that you can write about many times over. Spending time with friends is fun, but can you write about it 100 times over the next couple months? Maybe you can.

The most important thing is that you take the training and start learning. Right now, there are some puzzle pieces that haven't fit together in your "marketing mind". Later on, after you have done some training, you will have more and more ideas. I think it's very rare that a person picks the perfect niche on the first time. Maybe consider this a "practice niche", something to get you started and learning. Then a couple months down the road you can get your "real niche" and make and even better website with the skills you learned.

It's much easier to chose something that you're passionate or at least interested in. Think of a niche and then ask yourself whether you would enjoy writing about it in a week, a month, three months, six months and then a years time. If the answer is no at any stage I wouldn't touch it. It's much harder than people think to write about things you have no interest. People do it and it's a skill that can be learned, but I don't advise it along side learning all the other new things you will have to do.

It is important to an extent. You need to be at least somewhat knowledgeable or willing to research your niche so you can write good content for it. And self-help items (books, tapes, etc.) can be profitable if you promote it well. Actually many things can be profitable. There are millions of people out there searching for literally everything under the sun. You need to tap into a section of the population that are interested in the product or service that you are promoting. Hope that helps.