ATTINY45 and a relay in place of tactile switch (capacitive touch sensor)

Hello, this is my first post and my first original idea for a project involving Arduino.

First of all, I'm really new at all of this and the extent of my knowledge in electronics is basically V = IR.

Basically, what I'm trying to do, is to modify an unknown board that controls a flashlight. It has a tactile button that I want to replace with a capacitive touch sensor using the metal button as the contact point. The voltage going through the tactile button is reading over 5v so I planned on controlling a relay with an attiny45 to complete the circuit when the sensor is touched.

Is there anything crucial that I'm not considering? Or is there an easier way to achieve the same goal without needing a microcontroller?

Thanks for any help you can offer,

A small NPN transistor or opto-coupler across the tactile switch could do the switching. You still need a micro or some other circuit for the touch part. Leo..

You will need a touch sensor(TTP223B search it on google), Attiny45(which you already have) and a optocoupler(relay will also do the job) and a transistor(this is crucial since mcu cannot provide enough current to power on a relay, but mcu might work directly with optacoupler such as pc817). If you are making use of relay, transistor amplifier is crucial. So just hook them up, program it like when you touch mcu send a signal to transistor, it amplifies it and turns on relay switch of flashlight. I think this should help.