The Bible doesn't say suicide is a sin, that's people's interpretation. The claim is that murder is a sin, and suicide is murdering yourself, therefore suicide is a sin. I don't buy this argument, because in my view murder is taking someone's life against their will. If you kill someone who is begging to die I would call that euthanasia instead, and I don't see any reason that should be a sin.
I think the reality is that the sinfulness of an action falls along a continuum, not a binary true/false judgement. Suicide of an elderly person in great pain on the verge of death probably isn't sinful at all. Suicide of someone with severe mental illness in the midst of a crisis also doesn't seem sinful. Suicide of someone who is perfectly healthy, has children, and who is simply dissatisfied that they aren't wealthier and more beautiful seems very sinful. Other cases would fall somewhere along that spectrum.
If you feel everyone is connected, and you are physically and mentally able to contribute to making life better for people in some way, then I think the right thing to do may be to dedicate yourself to that. You might try getting into deep meditation to get closer to God and help work through your struggles and find a calling that resonates with you. You also might look into the Sikh religion, which believes in God along with reincarnation, for inspiration. Finding a purpose in life along with a community is where spirituality can really shine.
If you have the ability to contribute, but you have major struggles and decide to give up on life and commit suicide, then it may be sinful but that isn't the end of the story. Sins can be forgiven. God will also consider your other actions in life, so your entire life wouldn't be judged on a single action. It makes more sense to think of your life holistically, with death being just a piece of the bigger picture.
Personally I'm agnostic and I only believe in science and personal experience, not religion. I still believe there may be truth to religion, and regardless of the physical truth there are certainly valuable insights and practices in all religions. I think the best anyone can do is think carefully about their actions and be a good person to the best of their ability. If you stay true to that I think God or reincarnation will be good to you, even if you don't get everything right.