Why is there so much suffering in this world? Are we here in this world to suffer?

No, our Loving Father definitely didn't create us to suffer! Life is full of challenges, and it is up to us to use all of them to grow, to destine our fate. That’s why chazal teach us to bless Hashem for (what seems to us to be) good, as well as for (what seems to us to be) bad (Brachot 33b), because it’s really all for the good. You clearly have undergone hardships and challenges which would have easily brought others down to despair, self-pity, and pessimism. Instead, focus on the positive, and thank Hashem for His help. There’s a similar story of a Jew who wanted to learn how to deal with difficulties, so the Rebbe sent him to Rav Zusia, the poor. Upon his question, answered Rav Zusia, “I don’t know why the Rebbe sent you to me, for I have so many blessings from Hashem, and don’t have any difficulties!” In addition, Hashem is perfect and doesn’t “need” our prayers, just as He doesn’t need anything! Similarly, there is no one whom He doesn’t “want to bother with”. He cares about all His children, yet some of them prefer living in only the physical realm, and prefer their “reward” and pleasure in this world- so that’s what He gives them, while the more righteous can enjoy their reward sometimes in this world, and always in the world to come. Prayer is in place of the korbanot (sacrifices), which is from the word “karov”, for us to feel close to Him, which is one of the greatest levels and feelings that anyone can achieve. The closest we can understand about G-d, is like a parent who educates His child, through love and giving, but also through sometimes saying “No” or "Not now", and sometimes guiding us towards and through challenges that seem to be hard, but it’s all in our best interest. That’s part of His being perfect. In short, appreciate the good that He gives you, because many people don’t, and just focus on the “half-empty” cup. Thank G-d that you feel that direct connection with Him, for that is one of the main goals in life. More so, if you can use your positive and appreciative attitude, as well as your appreciation for the power and benefit of tfila (prayer), in order to help others overcome their challenges, you would mamash be “karov” and G-dly.