Losing streak is just normal period of poker playing. If you want to become a good poker player, stop being results orientated and enjoy playing (yeah, easy to say haha).
I have faced many downswings, and I have lost hope many times. So I know what are we talking about.
Nowadays I don't have any serious downswings anymore. What I do is this - I have learned to play different formats of poker, profitably - I play mtt's, Holdem cash, sit and go's,
spin and go's, heads up, PLO etc. I play only games I enjoy playing at that moment, and I lost my interest usually when I start losing money, then I just change game type. The most important thing is that I enjoy
playing itself, not making money. It is actually opposite, when I make a lot of money, it makes me nervous. I get most of satisfaction of making improvements and achieve new things.
I hope this answer helped.