Asking for help can be one of the hardest things to do in these situations, and you certainly aren't a failure for finding it difficult. I think your decision to ask for help here is a sign of a successful step in the right direction.
Are there methods of communicating your request for help that you are more comfortable with and less likely to pull out of? Apart from the obvious phone lines, many suicide crisis services have online chat or text message facilities.
If you are seeing a doctor or other professional in person, would it help to write down your feelings and then read it out or give it to them to read?
If you are weighing up who to tell about your feelings, remember you are very unlikely to be judged by a mental health professional, compared to family or friends who may not understand your situation.
Bear in mind that the flip-side of this is that telling a professional may lead to you being hospitalised if you are deemed to be a serious suicide risk.