If OP is in Germany, I can second this recommendation. They're funded via Christian organizations but as far as I'm aware the hotlines themselves are secular by default so if you're an atheist or non-Christian you don't have to worry about them pushing anything religious on you. Also, given how strict German privacy laws are, their claims of anonymity are as reliable as they can be (caveat: don't confess to any major crimes you have committed as those are usually not covered by privacy laws).

The easiest way to access a therapist is to ask your general practitioner (Hausarzt or Allgemeinmediziner) for a referral. You'll still have to find one yourself but they can direct you towards a list. The wait times can be very long but the sessions (and meds if any) are covered by public health insurance.