Is my vhs tape going to last the rest of my life ?

like all ferric magnetic tape formats, VHS has an organic binder that holds the metal oxide to the plastic.  the binder will fail even if you don't play the tape.  the most common failure mode is mold.  to avoid mold, tapes need to be stored in a very dry environment.  your best bet would be to transfer the video to a digital format, but remember even digital storage is not forever and best practice would be to renew digital media every 15 to 20 years.

For many years now VHS players have been considered obsolete, so in your old age you might not find a VHS player to play that tape on. And your particular tape might deteriorate long before your life does!

So I strongly suggest that you get that tape made into a DVD, and into a video file which can be stored on a computer and on an external storage device. There are companies which do that service for people, look for one locally. In that way you might be future-proof for a few decades.

 But keep your eye on the IT scene so that you can get even those more recent media converted to whatever comes along in 20 or 30 years or so.

transfer it to DVD, computer hard drive and/or an external hard drive before it decays or you can't find a working vcr

Chances are that there won't be any VHS players around anymore or will be very very difficult to find. You can get the VHS copied to a DVD or made into an MP4/AVI file which would last longer. VHS tapes can last a very long time however, the more they are used, the more the tape inside stretches and the more likely they'll snap and get caught inside the player. A DVD has it's own flaws as well. Too many scratches or a deep scratch can made them useless. Leaving either one in hot locations can damage them beyond repair. Look at transferring the video to a MP4/AVI file for longevity.

Sure, if you never watch it.

Your tape isn't going to last 50 years, but even if it did, what are you going to play it on?  You could keep a VHS player as well, but what will TV standards be like in 50 years?  Transferring the video to USB stick or DVD / Bluray isn't going to work either - they're not long term storage media (all the optical disk figures are projections) and you'll still have the problem of what you're going to play them on.  

Getting the tape digitised is relatively easy, but now you've got the problem of what codec to use.  X.264 is popular now, but it's a lossy compression and it's not future proof - in a few years time there'll be a new / better standard, nothing will play x.264 and you'll need to transcode, with all the loss of quality that goes with it.  And you'll have to keep doing that!

If you're serious about this you'll need to find a pro shop that will use good quality analog / digital converters and use a lossless codec.  Keep at least 2 separate copies and transcode them every few years so that you've always got copies that can be read with the current technology.

No tape can be counted on to last more than about 50 years, 

and (consumer-format) video tape is likely to be utterly useless after maybe 20 years.    

Your best bet is having it professionally transferred to a digital storage medium, preferably a USB stick. 

They degrade over time, you should have it transcribed onto a DVD

Very unlikely. I have some tapes that are about 12 years old that are OK, and some that stick together when playing, and the sound has almost faded away. Suggest that you transfer it to a different device, such as DVD or USB.

You can get it converted onto a DVD now.