HOw do I use the index as a reference instead of the date

Working with dates is an absolute nightmare. How do I select the index column instead of the dates column so that I can plot a linear regression line? The index column is numbered so I would like to reference the index against the price (instead of the date column)

I am getting this error message when trying to convert this column of strings so I choose to ignore it and use the index instead:

ValueError: could not convert string to float: '28/07/2017'

Here is the csv data:

           Date       Time     Open     High      Low     Last   Volume 
0    28/07/2017   00:00:00  1.12670  1.14067  1.12626  1.13833   245861   
1    31/07/2017   00:00:00  1.13892  1.14552  1.13356  1.14511   179706   
2    01/08/2017   00:00:00  1.14457  1.14514  1.13869  1.13973   162943 

Here is the code:

    #import libraries
    import pandas as pd
    import matplotlib.pyplot as plt
    from scipy import stats
    import numpy as np

    data = pd.read_csv('EURCHF_Daily.csv')  # load data set
    x = data.iloc[:, 0].values.reshape(-1, 1)  # values converts it into a numpy array
    x = x.astype(np.float)
    Y = data.iloc[:, 1].values.reshape(-1, 1)  # -1 means that calculate the dimension of rows, but have 1 column
    linear_regressor = LinearRegression()  # create object for the class
    linear_regressor.fit(X, Y)  # perform linear regression
    Y_pred = linear_regressor.predict(X)  # make predictions

plt.scatter(X, Y)
plt.plot(X, Y_pred, color='red')
plt.show()