What are some of the ways to be Emotionally stronger?

Emotional strength comes from knowing your own self

There are some ground rules that I have established for myself and I am happy to say that they have worked for me.

1. Having as less of interaction as possible with pessimists or narcissists as the company you keep most often tends to affect your mental and emotional state 
2. Spending more time with happy and peaceful souls as the company you chose to spend most of your time with is often time powerful enough to inspire or demotivate you 
3. Getting rid of the habit of arguing with people specially when the outcome is likely to be insignificant, as this is great energy waster and no good will spring forth from your investment of effort and time in arguing with them and trying to knock some sense into their heads
4. Meditating at least thrice a week for 15 minutes
5. Watch at least one feel-good movie every week (if you can watch it with your positive fellas as mentioned in point no. 2 above, cool. If not then better watch it alone)
6. Emotional strength comes from understanding your own self and specially knowing what triggers negative and positive emotions in you. Once you detect the external stimuli (a person, an event, a typical kind of behavior or a thing or absolutely anything) you can then move on and do a quick root cause analysis and understand what causes such a emotional reaction within yourself. In most cases you will find that some experience in your past or fear of a possible future ends up as the real culprit. Now all you need to work on is to LET GO of it. I would suggest you to try the Sedona Method (Google it to find more) to dissolve those mental and emotional blocks forever
7. Finally, keep yourself occupied with things that bring to you a greater amount of joy and peace in life. Once you are busy living the best version of 'yourself', you will have no time to entertain any kind of negativity in life.

Wishing you peace and happiness!!!