Money alone isn’t a guarantee to be successful. You need to take risk to achieve gains, and you need to build confidence and develop faith within you so can take things to its long term success. However, I don’t see these qualities with OP, that’s why it’s not surprising why despite of his wealth, he isn’t successful.
Although getting wealth is a kind of success, but you know deep within yourself that you still have more potentials to show so never limit yourself. Use your wealth to achieve more success in life, invest and reinvest, and eventually you’ll see that it’s easy for you to spend your wealth on cars, house and even international trips.
You are absolutely right, money alone can never guarantee that you are successful in life. Because money can finish anytime, but if you have plan and invest in many things that will be bringing you back profit that is when you can call your self successful person. because if you are not into any business or doing investment and you have wealth you will surly ended one day because if you are spending the money and you don't have anything returns you will end up a broke person.
So to be a successful person you need to have many plans that can be bringing double of your capital when you invest or do business, that you believe he can bring huge profit for you. You can have wealth and you can call your self a rich person but in few years, when you didn't set your target you will always end up losing all your wealth, because is just like you are just spending it to liabilities not using it for assets, that will bring more wealth to you.