Your feelings need to be acknowledged and owned, not denied and repressed. Remember the feelings you are experiencing are healthy and are actually part of the healing process. Mothers have different reactions to fathers about the homosexuality of their child. Loving your child is just loving your child. It does not mean that you are approving of their every decision.
Some guilt is genuine.
Owning up to involvement is not accepting blame. The child is responsible for their own sin before God. Join a parents support group, such as those run by Liberty Christian Ministries. It was written using materials from Liberty Christian Ministries. The articles can be freely downloaded and distributed.