"Not forsaking the assembling of yourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching" (Hebrews 10:25).
The bible does not need to have a minimum of 3 references in order for something to be true, God needs to only say it once and that is good enough for me and should be for you, hence the one scripture above.
The second way I would like to suggest that we DO need to go to church is...you find me someone who serves God in their daily life, in every aspect of their life, that has surrendered their entire selves to Christ in service to others and I you will also see that this person goes to church. Not that all people that go to church are that way but rather the reverse...all people that are that way go to church.
Unfortunately, people spend more time and effort trying to explain away their guilt in not seeking first the kingdom of God and one of those ways are by gathering together building each other up, holding each other accountable, and allowing God more opportunity to speak to you through other Christians.