I am worried my friend might fall into a depression or commit suicide if his crush rejects him, please help!?

Short version: My friend has a huge crush/obsession on a girl he barely knows and who will likely reject him. I think that will lead to him having depression and possibly going as far (although unlikely) as suicide.

My friend used to see this one girl at school, the last time was 5 months ago, since he switched schools after. He hasn't seen her since but he looks at her social media every day, probably every hour.

She doesn't know him at all and he has never talked to his crush. But he is obsessed and even said he thinks he loves her (I think it's just a very intense crush/obsession).

He says that him not being with her makes him sad. He is already quite troubled mentally and has been lonely for years. He has an extreme lack of confidence and as he said, he would get incredibly nervous around her, so i don't see how he would ever have a chance with her.

I still go to class with this girl, so now my friend is asking me to go talk to her and ask if she might be interested in him. I suspect she would not be interested in this guy who lacks confidence, has average looks and has been creeping on her (which she apparently noticed). Her not being interested or even just saying something like "I have a boyfriend" would absolutely crush him. I hink he would fall in a big depression (he says he has some "problems") or (unlikely, but remotely possible) suicide.

What can I do? Is there any way to soften the blow of him not getting to meet his crush?