Man counseling his female friend

Q: I am friends with a girl who is going through a lot of struggle mentally, this is happening since 2 years. I have been trying to help her and I have been listening to her cry most of the time. This has started affecting my mental health. As our Prophet (sallallahu alaihi wasallam) said to be there for a friend when the friend is sad and going through mental suffering. I wanted to know if it is right if I start distancing myself from her problems and start focusing on my mental health. She cries out to me and dumps her problems on my head and this is effecting me mentally. I just want to know if it will be right if I stop talking to her.

Buying shares in a company where 5% or less of the company investment is in haraam activities

Q: In order to buy stock shares, I have seen a ruling that says that only 5% or less of a company investment should be in haraam activities like alcohol, interest, etc. How can we say that when Allah has asked us to completely stay away from them? Will investing in Islamic banks be halaal if they follow these guidelines?

Pictures of silhouettes, limbs of a person and pictures with no face

Q: I draw and paint for a hobby but I am confused on this topic Islamically due to many different opinions. Is it permissible to:

1. Draw a full body picture without the eyes, nose and mouth?

2. Draw a limb on its own. (e.g. a hand holding a flower). But it is connected to the end of the paper. Does it have to be drawn severed?

3. Draw a full body with an umbrella covering the head?

4. Draw silhouettes of living creatures e.g. humans, birds, etc. (If this is not permissible then can I draw birds as a 'm' shape in the distance?)

Developing a social media app where people will post pictures

Q: I am a medical student who is also interested in web development, therefore I was thinking of developing a social media app similar to Facebook where people would be able to post photos. What I am concerned about is if people start to post immoral/obscene photos about which I am pretty sure they will on the website. Will I be sinning since I am providing a platform for such content??