Keep application from crashing when no database connection

Question

I have written a code which has a working database connection. I'm using phpmyadmin, so it's local. Everything works, except for when it doesn't have an active connection with the database; it just crashes. I've tried a timer which check for connection, but it still crashes.

My code so far:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;  
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
using HPJFRMS;

namespace HPJFRMS
{

public partial class HomeFRM : Form
{
    private string conn;
    MySqlConnection connect;
    string _naam = "";
    Form _Loginfrm;

    public HomeFRM(Form logFrom, string _name)
    {
        _Loginfrm = logFrom;
        InitializeComponent();
        lbWelkom.Text = "welkom " + _name;
        _naam = _name;
    }

    private void HomeFRM_Load(object sender, EventArgs e)
    {
        tmCheck.Enabled = true;
    }

    private bool Todo_ophalen()
    {
        db_connection();
        MySqlCommand cmd = new MySqlCommand();
        cmd.CommandText = "SELECT `todo` FROM `user` WHERE `username` LIKE '" + _naam + "'";
        cmd.Connection = connect;
        MySqlDataReader tdOphalen = cmd.ExecuteReader();
        if (tdOphalen.Read())
        {
            tbTodo.Text = tdOphalen.GetString(0);
            connect.Close();
            return true;
        }
        else
        {
            connect.Close();
            return false;
        }
    }

    private void db_connection()
    {
        try
        {
            conn = "Server=127.0.0.1;Database=users;Uid=root;Pwd=;";
            connect = new MySqlConnection(conn);
            connect.Open();
        }

        catch (MySqlException e)
        {
            tmCheck.Enabled = false;
            this.Hide();
            MessageBox.Show("Je bent offline! Het programma word afgesloten");
            this.Close();
        }
        finally
        {
            lbStatus.ForeColor = Color.Red;
        }
    }

    private void btBewerk_Click(object sender, EventArgs e)
    {
        if (btBewerk.Text == "Bewerken")
        {
            tbTodo.ReadOnly = false;
            btBewerk.Text = "Opslaan";

        }
        else
        {
            tbTodo.ReadOnly = true;
            btBewerk.Text = "Bewerken";
        }

    }

    private void button1_Click(object sender, EventArgs e)
    {
        this.Dispose();
    }

    private void tmCheck_Tick(object sender, EventArgs e)
    {
        bool T = Todo_ophalen();
        if (T)
        {
            lbStatus.ForeColor = Color.Green;
            lbStatus.Text = "Online";
        }
        else
        {
            lbStatus.ForeColor = Color.Red;
            lbStatus.Text = "Offline";
        }
    }