A lot depends on what this person has confided in you with IMHO. It just might be someone who is being abused and genuinely doesn't have anyone they can feel "safe" to talk to about it. If this person is getting overwhelming for you, it's best to let the person know and you can let this person know in a kind way too. Often the best way to do that is to let them know that you need to slow down because you get overwhelmed if that person dumps too much on you all at once. A person who is experiencing trauma can most definitely present with a lot all at once and just need someone they can trust to listen. Remind the person you are not a professional and that you can only problem solve and listen to a certain extent. You can also say to this person that given how overwhelmed they are that you really feel they should seek out a professional who knows more in how to help them find some resolve too.