This girl keeps on trying to accept God into my life or something, how do I decline without offending her?

[Underling]

So, I'm kinda new to my high school, and a couple days ago in homeroom I was talking to my friend about my dad (who recently got diagnosed with cancer but that's really beside the point) and the conversation eventually swung around to religion, and I told my friend that I was an atheist and I believed in observations of the natural world instead of faith/God.

Well, this really nice girl who sits behind me must've overheard, because later that day she wrote on my Facebook:
"Hi Cat, I know we don't really talk or hang out, but what you were saying in homeroom really affected me. I know you're going through a really hard time right now and you feel like God has abandoned you, but trust me he has NOT and he loves you, and if you turn to him, everything's gonna be all right, I'm praying for you, I hope you let God into your life, I think you should come to my church's Teen Club" and a whole bunch of other stuff like that. And then she invited me to sit with her at lunch, but the swung the convo around to religion and God.

I want to tell her that I don't believe in God and I politely decline, butI'm afraid I'll offend her, which of course I don't want to do. She's really sweet and I really appreciate her concern. What should I say?
Thanks in advance...

[Random Guy]

Thank you for your generous offer but I just need some time to myself.

[Methane Mama]

Well, I got tired of that kind of crap - after you've heard it a hundred times, or so, you will too - so, I just say this:

I am always amused when people pretend to speak for their imaginary friend - no matter what they're saying.

That usually shuts them up.

You could try reasoning with her about her beliefs, but that never works. You see, she has been brainwashed from an early age to believe that nonsense and you have no chance of reasoning her out of it. So, the only tools you have left at your disposal are rejection and/or open ridicule.

[GriMgriMoiRe]

Use the same arsenal for them. I used to be invited to church too, and i go there, give them a piece of my mind, after that, they wouldn't bother me anymore. That is, if you are really an atheist and not some hipster who knows nothing about being atheist.

[Mackey]

Just tell her. If you are polite and she gets upset, it is her fault, not yours. You already know that she is mentally unstable, so just be a nice and polite as you can be and expect that she will get upset.

[ToNi]

You still have to make it clear to her that you don't need her help. If she gets offended that's entirely her problem and as long as you tell her respectfully, then you have nothing to worry about. Your relationship with the universe is yours to choose and if you're an atheist or agnostic and that's exactly how you feel, then so be it!

[Georgio]

Tell her you hear voices telling you you're the Antichrist

[Caribbean Man]

Express your appreciation for her kind concern for you, then tell her kindly that you do not believe in the existence of God. Be respectful and kind stressing your appreciation for her kindness more so than the fact that you don't believe in God. You can also kindly preempt any future attempts by her to try to convert you by highlighting your respect for her right to her beliefs and your confidence that she would also respect your right to your belief (or lack thereof). You could say something like this:

"Jane, I really want to thank you for thinking about me and offering me support through your church. You really didn't have to do that yet you did. That was very kind of you, I appreciate it very much. Your thoughtfullness has certainly been consoling to me. But I must be honest with you by letting you know that I don't believe in a god because personally I haven't found any satisfactory evidence to support it. But I'm not going to try to convince you that there is no god because I respect your right to your beliefs just as I'm sure that you would respect my right to my non-belief. We can still hang out together as friends if you like. I would love to have a thoughtful and caring friend as you."

[Sperber]

If you are polite and saynothing offensive and she is still offended, than this is not your problem but her's. She made an offer, you decline. That's should be something absolutely normal betwenn civilised persons.